Question: What action does the Sidelink HARQ Entity take when it receives a Transport Block (TB) and associated Hybrid Automatic Repeat Request (HARQ) information in a subframe that corresponds to a new transmission opportunity on the SL-DCH?
Option 1: It allocates the received TB and HARQ information to a running Sidelink process.
Option 2: It discards the received TB and HARQ information if no Sidelink process is available.
Option 3: It allocates the received TB and associated HARQ information to a non-running Sidelink process and considers this transmission to be a new transmission.
Option 4: It ignores the received TB and HARQ information in this subframe.
Explanation: According to the MAC protocol specification, when the Sidelink HARQ Entity receives a TB and associated HARQ information in a subframe that corresponds to a new transmission opportunity on the SL-DCH, it allocates the received TB (if any) and the associated HARQ information to a non-running Sidelink process and considers this transmission to be a new transmission. This ensures proper handling of new transmissions and retransmissions in the sidelink communication.