Reference:
NAC (Network Access Control) is what the administrator should implement to ensure only approved systems can connect to switches in a private cloud environment. NAC is a security technique that controls and restricts access to network resources based on predefined policies or rules. NAC can verify and authenticate users or devices before granting them access to switches or other network devices. NAC can also enforce compliance and security standards on users or devices before allowing them to connect to switches.

Detailed
A . Data breaches: Laws and regulations such as GDPR and CCPA mandate organizations to inform users when their data has been compromised to maintain transparency and trust.
References:
CompTIA Cloud+ CV0-003 Study Guide Chapter 2: Security Requirements.

Mandatory access control (MAC) is a type of access control model that enforces strict security policies based on predefined rules and labels. MAC assigns security labels to subjects (users or processes) and objects (files or resources) and allows access only if the subject has the appropriate clearance and need-to-know for the object. MAC can mitigate the risk of users who have access to an instance modifying the system configurations, as it can prevent unauthorized or accidental changes to critical files or settings by restricting access based on predefined rules and labels. Reference: CompTIA Cloud+ Certification Exam Objectives, page 14, section 2.7

A CDN (content delivery network) is a system of distributed servers that deliver web content to users based on their geographic location, the origin of the web page, and the content delivery server1. A CDN can improve the user experience by reducing the latency, bandwidth, and load on the origin server. By offloading the images to an object storage, such as Google Cloud Storage or Amazon S3, the web application can save costs and improve performance by storing and serving the images from a CDN edge location that is closer to the user2. A CDN can also provide caching, compression, and security features for the web content3.

TCP port 3389 is the default port used by Remote Desktop Protocol (RDP) to connect to a remote system or application over a network. Opening TCP port 3389 on the firewall or network device will most likely solve the issue of users experiencing a connection timeout error when trying to use RDP to connect to an application, as it will allow RDP traffic to pass through. If TCP port 3389 is closed or blocked, RDP traffic will be denied or dropped, resulting in a connection timeout error. Reference: CompTIA Cloud+ Certification Exam Objectives, page 15, section 2.8