Question: What is the primary purpose of the 'OffsetTime' in Multimedia Broadcast/Multicast Service (MBMS) as per 3GPP standards, specifically in relation to a client's actions post-MBMS data transmission?
Option 1: To determine the optimal transmission power for subsequent MBMS sessions.
Option 2: To schedule the next MBMS data transmission in a multi-program environment.
Option 3: To measure the round-trip time (RTT) for potential unicast feedback.
Option 4: To specify the wait time before initiating the file repair procedure.
Explanation: The 'OffsetTime' dictates how long an MBMS client should wait after the end of an MBMS data transmission before starting the file repair procedure, acting as a timer for repair request suppression.