Explanation
The GREATEST drawback when using the AICPA/CICA Trust Services to evaluate a cloud service provider is the lack of specificity in the principles. This is because the AICPA/CICA Trust Services are a set of principles and criteria that provide guidance for evaluating and reporting on controls over information systems and services. However, the principles and criteria are very broad and generic, and do not address the specific risks and challenges that are associated with cloud services, such as data sovereignty, multi-tenancy, portability, etc. The other options are not drawbacks when using the AICPA/CICA Trust Services to evaluate a cloud service provider, but rather different aspects or benefits of using the AICPA/CICA Trust Services to evaluate a cloud service provider, such as compatibility (A), confidentiality C, or reporting (D).

Explanation
Trend/variance-detection tools are tools that look for anomalies in user behavior. These tools use statistical methods to establish a baseline of normal user activity and then compare it with current or historical data to identify deviations or outliers. These tools can help to detect unauthorized access, fraud, insider threats, or other malicious activities.

Explanation
The correct answer is C. SSH.
SSH stands for Secure Shell, a client-server program that opens a secure, encrypted command-line shell session from the Internet for remote logon. SSH allows users to remotely access and execute commands on a server without exposing their credentials or data to eavesdropping, tampering or replay attacks. SSH also supports secure file transfer protocols such as SFTP and SCP1.
VPN stands for Virtual Private Network, a technology that creates a secure, encrypted tunnel between two or more devices over a public network such as the Internet. VPN allows users to access resources on a remote network as if they were physically connected to it, while protecting their privacy and identity2.
IPsec stands for Internet Protocol Security, a set of protocols that provides security at the network layer of the Internet. IPsec supports two modes: transport mode and tunnel mode. Transport mode encrypts only the payload of each packet, while tunnel mode encrypts the entire packet, including the header. IPsec can be used to secure VPN connections, as well as other applications that require data confidentiality, integrity and authentication3.
SFTP stands for Secure File Transfer Protocol, a protocol that uses SSH to securely transfer files between a client and a server over a network. SFTP provides encryption, authentication and compression features to ensure the security and reliability of file transfers.
1: SSH (Secure Shell) 2: What is a VPN? How It Works, Types of VPN | Kaspersky 3: IPsec - Wikipedia :
[SFTP - Wikipedia]

Explanation
A security operations center (SOC) is a centralized unit that monitors, detects, analyzes, and responds to cyber threats and incidents in real time. A SOC enables continuous identification and mitigation of security threats to an organization by using various tools, processes, and expertise.

Explanation
Using a data loss prevention (DLP) solution to monitor data saved to a USB memory device is an example of managing data at rest. Data at rest is data that is stored on a device or media, such as hard disks, flash drives, tapes, or CDs. Data at rest can be exposed to unauthorized access, theft, or loss if not properly protected. A DLP solution is a tool that monitors and controls the movement and usage of data across an organization's network or endpoints. A DLP solution can prevent users from saving sensitive data to removable devices or alert on any violations of data policies.