Question: What is the purpose of the "R" bit in the MAC Random Access Response (RAR) payload for a UE that is not a BL UE or a UE in CE?
Option 1: To indicate the size of the UL Grant field.
Option 2: To indicate whether an UL Grant in RAR is for EDT.
Option 3: To signal the use of preamble format 2 for PRACH transmission.
Option 4: To request additional resources on the uplink.
Explanation: The "R" bit in the MAC RAR payload is set to "1" to indicate that an UL Grant in Random Access Response is for Enhanced Dedicated Channel (EDT) for a BL UE or a UE in CE. This allows the UE to differentiate between regular and EDT transmissions, ensuring proper handling of the uplink grant.