Secure coding practices are the best way to prevent cross-site scripting (XSS) attacks, because they can ensure that the web application validates and sanitizes user input and output data to prevent malicious scripts from being executed on the web browser. XSS attacks are a type of web application vulnerability that exploit the lack of input validation or output encoding in web pages that accept user input or display dynamic content. Application firewall policy settings, a three-tier web architecture, and use of common industry frameworks are not effective controls to prevent XSS attacks, because they do not address the root cause of the vulnerability in the web application code. References: CISA Review Manual (Digital Version), Chapter 5, Section 5.4.2

Application containers are a form of operating system virtualization that share the same kernel as the host operating system. This means that any vulnerability or compromise in the kernel can affect all the containers running on the same host, as well as the host itself. Additionally, containers may have privileged access to the kernel resources and functions, which can pose a risk of unauthorized or malicious actions by the container processes. Therefore, securing the kernel is a critical aspect of application container security.
Shared registries (option A) are not an inherent risk in the application container infrastructure, but they are a potential risk that depends on how they are configured and managed. Shared registries are repositories that store and distribute container images. They can be public or private, and they can have different levels of security and access controls. Shared registries can pose a risk of exposing sensitive data, distributing malicious or vulnerable images, or allowing unauthorized access to images. However, these risks can be mitigated by using secure connections, authentication and authorization mechanisms, image signing and scanning, and encryption.
Host operating system (option B) is not an inherent risk in the application container infrastructure, but it is a potential risk that depends on how it is configured and maintained. Host operating system is the underlying platform that runs the application containers and provides them with the necessary resources and services.
Host operating system can pose a risk of exposing vulnerabilities, misconfigurations, or malware that can affect the containers or the host itself. However, these risks can be mitigated by using minimal and hardened operating systems, applying patches and updates, enforcing security policies and controls, and isolating and monitoring the host.
Shared data (option C) is not an inherent risk in the application container infrastructure, but it is a potential risk that depends on how it is stored and accessed. Shared data is the information that is used or generated by the application containers and that may be shared among them or with external entities. Shared data can pose a risk of leaking confidential or sensitive data, corrupting or losing data integrity, or violating data privacy or compliance requirements. However, these risks can be mitigated by using secure storage solutions, encryption and decryption mechanisms, access control and auditing policies, and backup and recovery procedures.
Therefore, option D is the correct answer.
References:
* Application Container Security Guide | NIST
* CSA for a Secure Application Container Architecture
* Application Container Security: Risks and Countermeasures

The best recommendation for the IS auditor to make is to implement a closing checklist, as this will help to ensure that all the required tasks and scripts are performed and verified during the year-end closing process12. A closing checklist can also help to prevent errors, omissions, and delays that could affect the accuracy and timeliness of the financial statements3 .
References
1: Year-end closing procedures for GL - Dynamics GP | Microsoft Learn1 2: Year-end activities FAQ - Finance | Dynamics 365 | Microsoft Learn2 3: Year-End Closing Checklist: 10 Steps to Close Your Books3 :
Year End Closing Checklist: 7 Steps to Make it Easy

The most important aspect of an application development acceptance test is that user management approves the test design before the test is started, as this ensures that the test objectives, criteria, and procedures are aligned with the user requirements and expectations. The programming team's involvement in the testing process, the testing of data files for valid information before conversion, and the quality assurance (QA) team' s charge of the testing process are also important, but they are not as critical as user management's approval of the test design. References: CISA Review Manual (Digital Version), Chapter 4, Section 4.4.2

The type of IS audit that would provide the greatest level of assurance that the department's objectives have been met after implementing new technologies and processes is an integrated audit. An integrated audit is an audit that combines financial, operational, compliance, and IT auditing aspects to provide a holistic view of the organization's performance and risks. An integrated audit can evaluate whether the new technologies and processes are aligned with the organization's goals, strategies, policies, and controls, and whether they are delivering value, efficiency, effectiveness, and reliability. The other types of IS audits (A, C and D) would not provide the same level of assurance, as they would only focus on specific aspects of the organization's activities, such as performance, cyber security, or financial reporting, which may not capture the full impact of the new technologies and processes. References: CISA Certification | Certified Information Systems Auditor | ISACA, CISA Review Manual (Digital Version), Chapter 1: The Process of Auditing Information Systems, Section 1.2: Types of IS Audit Engagements