question: What is the purpose of the wireless grant-free data plane in the SD-VEC infrastructure? option 1: To provide multi-user detection techniques for contention-free wireless access option 2: To ensure reliability and physical error-rate performance in vehicular communications option 3: To enable automatic task allocations between edge ANs and the cloud option 4: To facilitate proactive access between vehicles and APs option 5: To support dynamic radio resource assignments among virtual clusters 