Which items should be checked during the PMCS before operating the Truck?

The primary focus of the preventive maintenance checks and services (PMCS) is to ensure that the vehicle is safe and operational before use. The correct choice emphasizes the critical areas that need to be inspected, which include fluids, instruments, brakes, and mirrors.

Fluids must be checked to ensure there are no leaks and that levels are adequate for safe operation. Instruments provide vital information about the vehicle’s functioning status, including oil pressure and temperature readings. Brakes are essential for safety, as their integrity directly affects the vehicle's ability to stop effectively. Mirrors are crucial for situational awareness and ensuring safe maneuverability, especially in tactical environments where visibility can be compromised.

The other options present lists of items that are important in their own right, but do not encompass all critical aspects tied to immediate safety and operational readiness as effectively as the selected choice. Safeguarding these key components prior to vehicle operation supports both personnel safety and operational success in dynamic situations.