The nslookup command is a network administration tool used for querying the Domain Name System (DNS) to obtain domain name or IP address mapping or for any other specific DNS record. It's the most direct way to verify if a PC can resolve a website's domain name to its IP address.
Here's why the other options are not the primary tools for this task:
* B. hostname: This command displays the hostname of the computer.
* C. tracert: This command traces the route packets take to reach a specific destination. It can help identify network connectivity issues but doesn't directly test DNS resolution.
* D. netstat: This command displays active network connections and listening ports. It's not used for DNS troubleshooting.
How to use nslookup:
* Open a command prompt.
* Type nslookup <website address> (e.g., nslookup google.com) and press Enter.
* The output will show the DNS server used and the IP address(es) associated with the website.
* If the command returns an error or doesn't show an IP address, it indicates a problem with DNS resolution.

Detailed Explanation with Core 2 References:Bollards are physical barriers that prevent unauthorized vehicle access to certain areas, providing a preventive measure against unauthorized entry and potential threats.
Bollards are classified as a preventive control because they act to deter or block physical access to secured locations, as opposed to video surveillance or alarm systems, which are typically used for detection and monitoring. Core 2 highlights the importance of implementing various physical security controls to protect assets and infrastructure (Core 2 Objective 2.1).

Calibrating the phone sensors is a step that can troubleshoot the issue of screen not autorotating on a mobile device. Screen autorotation is a feature that automatically adjusts the screen orientation based on the device's position and movement. Screen autorotation relies on sensors such as accelerometer and gyroscope to detect the device's tilt and rotation. Calibrating the phone sensors can help fix any errors or inaccuracies in the sensor readings that may prevent screen autorotation from working properly. Enabling the touch screen, reinstalling the operating system, and replacing the screen are not steps that should be done next to troubleshoot this issue.

Browser plug-ins are software components that add functionality to a web browser, such as playing videos, displaying animations, etc. However, some browser plug-ins can also be malicious or compromised and cause unwanted pop-up advertising messages while browsing the internet. A malware scan may not be able to locate the source of the infection if it is hidden in a browser plug-in. Windows updates, DNS settings and certificate store are not likely sources of pop-up advertising messages. Verified References: https://www.comptia.org
/blog/browser-security https://www.comptia.org/certifications/a

The next step after isolating the system is to perform a system scan to remove the malware (Option C). Since ransomware is suspected, running a comprehensive malware scan can help identify and remove the malicious software. It is crucial to deal with the active threat before taking further actions.
* Scheduling an antivirus scan and system update (Option A) may help, but the immediate concern is identifying and removing the ransomware.
* Educating the end user (Option B) is important but should happen after the immediate threat is resolved.
* Creating a system restore point (Option D) would not be useful at this point since the system is infected.
CompTIA A+ Core 2 References:
* 2.3 - Detect, remove, and prevent malware, including handling ransomware.