Question: In a 3GP file with SRTP recording extensions, how are MIKEY MBMS Traffic Key messages stored and linked to SRTP reception hint tracks?
Option 1: Stored in 'cdsc' tracks and linked via 'oksd' track references
Option 2: Stored in 'oksd' STKM tracks and linked to SRTP reception hint tracks via 'cdsc' track references
Option 3: Embedded directly within SRTP reception hint tracks without a separate STKM track
Option 4: Stored in a dedicated 'srtp' track with automatic linking to relevant reception hint tracks
Explanation: This is correct because MIKEY MBMS Traffic Key messages are stored in OMA BCAST STKM tracks labeled as 'oksd'. These STKM tracks are linked to SRTP reception hint tracks using 'cdsc' track references, ensuring a connection between key messages and relevant SRTP tracks for proper decryption and playback.