Explanation
An increase in false negatives would be of greatest concern when reviewing the performance of an organization's IDSs, because it means that the IDSs are failing to detect and alert on actual attacks that are occurring on the network. False negatives can lead to serious security breaches, data loss, reputational damage, and legal liabilities for the organization. False positives, on the other hand, are alerts that are triggered by benign or normal activities that are mistaken for attacks. False positives can cause annoyance, inefficiency, and desensitization, but they do not pose a direct threat to the security of the network. Therefore, a decrease in false positives would be desirable, and an increase in false positives would be less concerning than an increase in false negatives.
References = CISM Review Manual, 16th Edition, page 2231; Intrusion Detection Systems | NIST

Section: INFORMATION SECURITY GOVERNANCE
Explanation:
Policies define security goals and expectations for an organization. These are defined in more specific terms within standards and procedures. Standards establish what is to be done while procedures describe how it is to be done. Guidelines provide recommendations that business management must consider in developing practices within their areas of control; as such, they are discretionary.

An effective information security awareness training program should aim to improve the knowledge, skills and behavior of the employees regarding information security. One of the ways to measure the effectiveness of such a program is to conduct phishing simulations, which are mock phishing attacks that test the employees' ability to identify and report phishing emails. An increase in the identification rate during phishing simulations indicates that the employees have learned how to recognize and avoid phishing attempts, which is one of the common threats to information security. Therefore, this is the best indication of an effective information security awareness training program among the given options.
The other options are not as reliable or relevant as indicators of an effective information security awareness training program. An increase in the frequency of phishing tests does not necessarily mean that the employees are learning from them or that the tests are aligned with the learning objectives of the program. An increase in positive user feedback may reflect the satisfaction or engagement of the employees with the program, but it does not measure the actual learning outcomes or behavior changes. An increase in the speed of incident resolution may be influenced by other factors, such as the availability and efficiency of the incident response team, the severity and complexity of the incidents, or the tools and processes used for incident management. Moreover, the speed of incident resolution does not reflect the prevention or reduction of incidents, which is a more desirable goal of an information security awareness training program. Reference = CISM Review Manual, 16th Edition, ISACA, 2022, pp. 201-202, 207-208.
CISM Questions, Answers & Explanations Database, ISACA, 2022, QID 1001.