FAA AMT Airframe Test 2025 – 400 Free Practice Questions to Pass the Exam

The question asks about the proper way to mark and graduate aircraft instruments, which indicates that a specific set of instructions or guidelines must be followed. Option A refers to the manufacturer's guidelines, which may vary from one manufacturer to another and may not necessarily be consistent across all aircraft models. Option B refers to federal regulations, which may outline general guidelines but may not provide specific instructions for each type of aircraft instrument. Option D refers to international standards, which may also vary from country to country and may not specifically address all aircraft instruments. Option C, the specific aircraft maintenance or flight manual, is the most appropriate because it provides detailed instructions for marking and graduating each instrument according to its type and model. Therefore, it is important to follow the specific manual for each aircraft to ensure accuracy and safety.