Question: What is the primary purpose of the 'BookmarkList' element in the context of Transparent end-to-end Packet-switched Streaming Service (PSS)?
Option 1: To store and manage user bookmarks, utilizing attributes such as UserID, ContentURI, and time.
Option 2: To facilitate real-time streaming between PSS clients and servers.
Option 3: To handle HTTP requests for public bookmark access across all PSS clients.
Option 4: To parse XML documents for BookmarkListResponse messages.
Explanation: The 'BookmarkList' element is primarily used for storing and managing user bookmarks, incorporating essential attributes like UserID, ContentURI, and time to identify and manage individual user bookmarks within the PSS framework.