The data dictionary in a database contains metadata about the database objects such as tables, views, indexes, and users. The statement that views with the prefix ALL_, DBA_, and USER_ are not all available for every type of metadata is true because these views provide metadata with different levels of access based on user privileges. The statement that views with the prefix ALL_ display metadata for objects to which the current user has access is also true because ALL_ views show information about database objects accessible to the specific user querying the data dictionary. These views are critical for managing and administering database permissions and schemas.