Explanation
An application whitelisting policy is a set of rules that specifies which applications are allowed to run on a system or a network. Application whitelisting is a security technique that can prevent unauthorized or malicious software from executing, and it is often used in VDI (Virtual Desktop Infrastructure) environments to provide end users with access to limited applications. A cloud administrator who is responsible for managing a VDI environment should make changes to the application whitelisting policy when a new application needs to be provided, as this would ensure that the new application is authorized and compatible with the VDI environment.

Explanation
MFA (Multi-Factor Authentication) is a security technique that requires the user to present two or more pieces of evidence to prove their identity when they try to access a system or an application. For example, a password and a physical token, or a fingerprint and a one-time code. MFA can improve the company's security posture by preventing unauthorized access even if the password or single-factor authentication is compromised, as the attacker would also need to have the other factors to log in. According to the web search results, MFA can prevent 99.9% of account attacks1.
SSO (Single Sign-On) is a system that allows the user to use one set of login credentials to access multiple systems and applications that previously may have each required their own logins. SSO can improve productivity and user convenience, but it does not replace MFA. In fact, SSO works in conjunction with MFA, as it can enforce MFA for all the systems and applications that are integrated with SSO2. Therefore, implementing SSO does not mean that MFA is not needed.

Explanation
The inbound rule that the security team identified as a potential vulnerability is the one that allows SSH access (port 22) from any source (0.0.0.0/0). This means that anyone on the internet can try to connect to the Linux servers using SSH, which poses a risk of unauthorized access or brute-force attacks. The cloud administrator, who is working remotely, logs in to the cloud management console and modifies the rule to set the source to
"My IP". This means that only the administrator's IP address can connect to the Linux servers using SSH, which improves the security of the servers. However, this also prevents other authorized users, such as the internal developer, from accessing the servers using SSH, as they have different IP addresses than the administrator. Therefore, the administrator needs to modify the rule again to allow more sources for SSH access.
The best option for both the developer and the administrator to access the server from their locations is to modify the inbound rule to allow the company's external IP address as a source. This means that only the IP addresses that belong to the company's network can connect to the Linux servers using SSH, which reduces the attack surface and ensures that only authorized users can access the servers. The company's external IP address can be obtained by using a web service such as [What Is My IP Address?] or [IP Location]. The administrator can then enter this IP address or its CIDR notation in the source field of the inbound rule.

Explanation
Tags are metadata or labels that can be assigned to cloud resources or services to identify and organize them based on various criteria, such as name, purpose, owner, or cost center. Tags can help track the costs for each business unit or department that uses cloud services, as they can enable granular and accurate billing and reporting based on the tags. Misconfigured tags can cause the issue of inaccurate cost tracking for different businesses, as they can result in incorrect or missing billing information or reports. The issue can be resolved by configuring the tags properly to reflect the correct business unit or department for each cloud resource or service. References: CompTIA Cloud+ Certification Exam Objectives, page 13, section 2.5

Explanation
The best options to implement for a public cloud solution for an existing application using lift and shift that requires scalability and external access are a load balancer and a VPN (virtual private network). A load balancer is a device or service that distributes incoming traffic across multiple servers or instances based on various criteria, such as availability, capacity, or performance. A load balancer can improve scalability by balancing the workload and optimizing resource utilization. A VPN is a technology that creates a secure and encrypted connection over a public network, such as the internet. A VPN can provide external access by allowing remote users or sites to connect to the cloud resources as if they were on the same private network.
Reference: CompTIA Cloud+ Certification Exam Objectives, Domain 1.0 Configuration and Deployment, Objective 1.4 Given a scenario, execute a provided deployment plan.