Which two places can an app builder go to see a list of available Custom...

The correct answers are C. Lightning App Builder and D. Lightning components in Setup.

In Lightning App Builder, custom Lightning components that are configured for use in Lightning App Builder appear in the Lightning Components pane.

In Setup → Lightning Components, Salesforce allows admins to view a list of Lightning Web Components and Aura components in the org.

Why others are incorrect:

A. Visualforce components in Setup lists Visualforce custom components, not Lightning components.

B. Salesforce Optimizer App analyzes org configuration and recommendations; it is not the place to list available custom Lightning components.

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