Which of the following is a required procedure of the pre-trip inspection?

Answer: A — Perform a break test

Performing a break test is a required procedure of the pre-trip inspection as it ensures the brakes are functioning properly and safe to use while driving. Option B, inspecting the battery, may also be a required procedure, but it is not specifically mentioned in the question. Option C, checking tire pressures, is an important step in the pre-trip inspection but it is not the only required procedure. Option D, checking the alignment of the steering system, may also be important but it is not specifically mentioned as a required procedure in the question. Therefore, A is the most accurate choice among the given options.