The rules imposed by the Office of Foreign Assets Control (OFAC) for legal entities and persons related to the US are:
Nationals of the US must comply with OFAC rules, regardless of where they are located in the world. This means that US citizens, permanent residents, and entities organized under US law are subject to OFAC sanctions and prohibitions, even if they operate or reside outside the US12.
Any foreign corporation is also penalized if it conducts transactions with sanctioned countries under OFAC rules. This means that non-US entities that engage in trade or financial dealings with OFAC-designated countries, entities, or individuals are liable to face civil or criminal penalties, as well as secondary sanctions that could restrict their access to the US market or financial system34.
The other options are not correct, because:
A subsidiary of a legal entity of the US, which is formally registered in a foreign country, is not exempt from OFAC rules. This means that foreign-incorporated entities that are owned or controlled by US persons or entities are also subject to OFAC sanctions and prohibitions, unless they are specifically authorized or licensed by OFAC12.
A foreign individual visiting the US for a short vacation is not obligated to follow OFAC rules. This means that non-US persons who are temporarily present in the US are not subject to OFAC sanctions and prohibitions, unless they are involved in transactions that have a US nexus or violate other US laws.
The head office of a foreign legal entity which has a branch in the US does not need to comply with OFAC rules. This means that non-US entities that have a presence or operation in the US are not subject to OFAC sanctions and prohibitions, unless they are involved in transactions that have a US nexus or violate other US laws.
Reference:
ACAMS CAMS Certification Video Training Course - Exam-Labs3
Exam CAMS: Certified Anti-Money Laundering Specialist (the 6th edition)4 ACAMS Study Guide for the Certification Examination, 6th Edition, Chapter 7, page 147: https://www.acams.org/wp-content/uploads/2019/08/ACAMS-Study-Guide-6th-Edition-Chapter-7.pdf ACAMS Study Guide for the Certification Examination, 6th Edition, Chapter 7, page 148: https://www.acams.org/wp-content/uploads/2019/08/ACAMS-Study-Guide-6th-Edition-Chapter-7.pdf ACAMS Study Guide for the Certification Examination, 6th Edition, Chapter 7, page 149: https://www.acams.org/wp-content/uploads/2019/08/ACAMS-Study-Guide-6th-Edition-Chapter-7.pdf

Customer composition and product offerings are two important factors that affect the level of risk exposure for a financial institution (FI) in terms of money laundering and terrorist financing. Customer composition refers to the types of customers that the FI serves, such as individuals, businesses, non-profit organizations, or politically exposed persons (PEPs). Different customer segments may pose different levels of risk depending on their activities, sources of funds, geographic locations, and connections to other entities. For example, customers that are cash-intensive, have complex ownership structures, operate in high-risk jurisdictions, or are associated with PEPs may present higher risk indicators than customers that are transparent, regulated, and operate in low-risk jurisdictions12. Product offerings refer to the types of products, services, and transactions that the FI provides, such as deposits, loans, wire transfers, trade finance, or digital assets. Different products, services, and transactions may have different levels of vulnerability to money laundering and terrorist financing depending on their features, complexity, volume, and speed. For example, products that are anonymous, involve high-value or cross-border transfers, enable rapid movement of funds, or involve new or emerging technologies may present higher risk indicators than products that are identifiable, involve low-value or domestic transfers, require multiple verification steps, or involve established or traditional technologies12.
Reference:
1: Risk Assessment: Risk Factors & Mitigating Measures2
2: Risk Assessment: Process, Examples, & Tools1

A politically exposed person (PEP) is a customer who requires the most enhanced due diligence (EDD). This is because PEPs are individuals who hold or have held prominent public positions, such as heads of state, senior politicians, judges, military officers, or directors of state-owned enterprises, and who may pose a higher risk of money laundering, corruption, or bribery due to their influence and access to public funds1. EDD measures for PEPs may include obtaining senior management approval, establishing the source of wealth and funds, and conducting enhanced ongoing monitoring of the business relationship2.
The other customers listed do not necessarily require the most EDD, although they may still present a higher risk of money laundering depending on the circumstances. A resident of a non-cooperative jurisdiction is a customer who lives in a country or territory that has been identified by the Financial Action Task Force (FATF) or other international bodies as having weak or deficient anti-money laundering (AML) standards or posing a threat to the international financial system3. EDD measures for such customers may include obtaining additional information or documentation, applying extra scrutiny to transactions, or refusing to establish or continue the business relationship4. An international business corporation is a customer who operates in multiple jurisdictions and may have complex or opaque ownership structures that can conceal the identity or activity of the beneficial owners or controllers. EDD measures for such customers may include verifying the legal existence and structure of the entity, identifying the beneficial owners and controllers, and understanding the nature and purpose of the business relationship. An established customer is a customer who has a long-standing and regular business relationship with the financial institution and who may have a lower risk of money laundering due to the familiarity and trust that has been built over time. EDD measures for such customers may not be required unless there are changes in the customer's profile, behavior, or risk level.
Reference:
1: Politically Exposed Persons (Recommendations 12 and 22) - FATF1 2: High-risk customers, including politically exposed persons | FCA2 3: High-Risk and Other Monitored Jurisdictions - FATF3 4: Your responsibilities under money laundering supervision | GOV.UK4 : International Business Corporations - ACAMS : Anti-Money Laundering Customer Due Diligence | Veriff.com : Customer Due Diligence - ACAMS : Anti-money laundering - a guide to customer due diligence

Money laundering and terrorist financing are both forms of financial crime that involve the movement of illicit funds. However, they differ in the source and purpose of the funds. Money laundering is the process of disguising the origin, ownership, or destination of funds that are derived from illegal activities, such as drug trafficking, fraud, or tax evasion. Terrorist financing is the provision or collection of funds, by legitimate or illegitimate means, for the purpose of carrying out terrorist acts. Therefore, the anti-money laundering specialist should consider the following factors in developing a compliance program:
Related practices are used to conceal the nature of the funds. Both money launderers and terrorist financiers use similar methods to hide the true identity, source, or destination of the funds, such as using shell companies, front organizations, complex transactions, cash couriers, or cryptoassets. A compliance program should include measures to identify and verify the customers, beneficial owners, and counterparties involved in the transactions, as well as to monitor and report any suspicious or unusual activities.
Similar techniques are used to move funds. Both money launderers and terrorist financiers use the same stages of placement, layering, and integration to move funds through the financial system. Placement is the introduction of illicit funds into the legitimate financial system, such as by depositing cash, purchasing assets, or transferring funds electronically. Layering is the separation of the funds from their source, such as by using multiple accounts, jurisdictions, or intermediaries. Integration is the re-entry of the funds into the legitimate economy, such as by investing in businesses, real estate, or securities. A compliance program should include measures to detect and prevent the movement of illicit funds through the financial system, such as by applying risk-based due diligence, record-keeping, and transaction limits.
Reference:
CAMS Certification Package - 6th Edition | ACAMS
CAMS Certifications: How to Get CAMS Certified | ACAMS
ACAMS CAMS Certification Video Training Course - Exam-Labs
Exam CAMS: Certified Anti-Money Laundering Specialist (the 6th edition)

According to the Anti-Money Laundering Specialist (the 6th edition) resources, one of the challenges of online financial technologies is the difficulty of verifying the identity and legitimacy of the customers and counterparties. This creates opportunities for money launderers and other criminals to exploit the anonymity and speed of online transactions to move and conceal illicit funds. The other options are not directly related to the money laundering risk posed by online financial technologies.
Reference:
: ACAMS Study Guide for the Certified Anti-Money Laundering Specialist (the 6th edition), Chapter 5: Risk-Based Approach, page 133.
: ACAMS Study Guide for the Certified Anti-Money Laundering Specialist (the 6th edition), Chapter 7: Money Laundering Risks and Methods, page 203.