Explanation
According to the Splunk Enterprise Security documentation, the Use Case Library is a feature that contains scenarios that are useful during ES implementation. The Use Case Library provides a collection of Analytic Stories that provide actionable guidance for detecting, analyzing, and addressing security threats. An Analytic Story contains the searches, data sources, and explanations that you need to implement the scenario in your own ES environment. The Use Case Library also allows you to explore, activate, bookmark, and configure the searches that are related to each Analytic Story. You can filter the Analytic Stories by industry use cases, frameworks, or data sources. The Use Case Library helps you to quickly and easily deploy the most relevant security content for your organization. Therefore, the correct answer is A. Use Case Library. References
= Manage Analytic Stories through the use case library in Splunk Enterprise Security.
Splunk Enterprise Security: SIEM Use Case Library | Splunk