Question: What is the primary purpose of the 'Deliver_UL_Message' service operation in V2X Application Enabler (VAE) Services?
Option 1: To establish a secure connection between the VAE server and the service consumer.
Option 2: To deliver uplink messages from the service consumer to the VAE server for further processing.
Option 3: To manage subscription settings for V2X-related services on the part of the service consumer.
Option 4: To handle errors occurring during message transmission in V2X communications.
Explanation: The correct answer, Option 2, aligns with the described functionality of the 'Deliver_UL_Message' service operation, which is specifically designed to deliver uplink messages. This operation plays a crucial role in facilitating communication from the service consumer (e.g., a vehicle's onboard unit) back to the VAE server, enabling various V2X applications such as sharing traffic updates or hazard warnings.