Explanation/Reference:
Profiles are, in many ways, similar to manifests in that they use the same XML DTD. However, instead of providing information about a service, its dependencies, and methods, a profile is used to provide customization of a service or an instance of a service. Customizations include whether an instance of a service should be enabled or disabled and any modifications to service configuration properties.
Incorrect:
Not A: Manifests (not profiles) are used to describe services and instances of a service, including any property groups and properties they might have.