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 webpages 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 controlsto 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

The auditor should be most concerned about the security policy documents being available on a public domain website. This is because this exposes the organization's security posture and strategy to potential attackers, who can exploit the information to launch targeted attacks or bypass the security controls. The security policy documents should be classified as confidential and protected from unauthorized access or disclosure. The other options are less severe than exposing the security policy documents to the public, although they may also indicate some gaps or weaknesses in the security policy development, implementation, or maintenance process. References:
* CISA Review Manual (Digital Version), Chapter 5, Section 5.31
* CISA Online Review Course, Domain 3, Module 1, Lesson 12

The primary benefit of automating application testing is to provide test consistency. Automated testing can ensure that the same test cases are executed in the same manner and order every time, which can improve the reliability and accuracy of the test results. Providing more flexibility, replacing all manual test processes, and reducing the time to review code are possible benefits of automating application testing, but they are not the primary benefit. References:
ISACA, CISA Review Manual, 27th Edition, 2020, p. 3091
ISACA, CISA Review Questions, Answers and Explanations Database - 12 Month Subscription

A balanced scorecard is a strategic planning framework that companies use to assign priority to their products, projects, and services; communicate about their targets or goals; and plan their routine activities1. The scorecard enables companies to monitor and measure the success of their strategies to determine how well they have performed. A balanced scorecard for IT management can help assess IT functions and processes by defining four perspectives: financial, customer, internal business process, and learning and growth2. These perspectives can help IT management align their IT objectives with the organization's vision and mission, identify and prioritize the key performance indicators (KPIs) for IT, and evaluate the effectiveness and efficiency of IT operations and services3.
References
1: Balanced Scorecard - Overview, Four Perspectives 2: The IT Balanced Scorecard (BSC) Explained - BMC Software 3: A BALANCED SCORECARD (BSC) FOR IT PERFORMANCE MANAGEMENT - SAS Support

The greatest concern to an IS auditor reviewing an organization's method to transport sensitive data between offices is that the method relies exclusively on the use of asymmetric encryption algorithms. Asymmetric encryption algorithms, also known as public key encryption, use two different keys for encryption and decryption: a public key that is shared with anyone who wants to communicate with the sender, and a private key that is kept secret by the sender. Asymmetric encryption algorithms are more secure than symmetric encryption algorithms, which use the same key for both encryption and decryption, but they are also slower and more computationally intensive. Therefore, relying exclusively on asymmetric encryption algorithms may not be efficient or practical for transporting large amounts of sensitive data between offices. A better method would be to use a combination of symmetric and asymmetric encryption algorithms, such as using asymmetric encryption to exchange a symmetric key and then using symmetric encryption to encrypt and decrypt the data.
The other options are not as concerning as option C. The method relying exclusively on the use of public key infrastructure (PKI) is not a concern, because PKI is a system that provides the services and mechanisms for creating, managing, distributing, using, storing, and revoking digital certificates that are based on asymmetric encryption algorithms. PKI enables secure and authenticated communication between parties who do not have a prior trust relationship. The method relying exclusively on the use of digital signatures is not a concern, because digital signatures are a way of verifying the authenticity and integrity of a message or document by using asymmetric encryption algorithms. Digital signatures ensure that the sender cannot deny sending the message or document, and that the receiver can detect any tampering or alteration of the message or document. The method relying exclusively on the use of 128-bit encryption is not a concern, because 128-bit encryption is a level of encryption that uses a 128-bit key to encrypt and decrypt data. 128-bit encryption is considered to be strong enough to resist brute-force attacks by modern computers. References: Asymmetric vs Symmetric Encryption: What are differences?, Public Key Infrastructure (PKI), Digital Signature, What is
128-bit Encryption?