What is the function of the RAT (Ram Air Turbine) in the system?

The function of the Ram Air Turbine (RAT) is to serve as an emergency power source. In the event of loss of electrical power from the engines or other systems, the RAT deploys automatically or can be manually deployed to harness airflow. This airflow powers the RAT and generates hydraulic power, which is crucial for operating essential flight systems such as flight controls and backup instruments. The RAT is particularly important during critical situations where maintaining control and functionality of the aircraft is necessary for safety.

While the other options mentioned may relate to other systems on the aircraft, they do not accurately reflect the primary role of the RAT. The RAT is specifically designed to provide hydraulic and electrical power in emergencies, which is why option B is the correct choice.