Which activities are included in the term maintenance?

• A. Testing only
• B. Calibration and alignment
• C. Inspection, parts replacement, repair, and overhaul
• D. Lubrication and cleaning

Answer: (C)

Maintenance is the broad set of activities that keep an engine and its systems in serviceable condition, covering everything from routine checks to restoring the unit to like-new performance. The reason the full set—inspection, parts replacement, repair, and overhaul—is the best answer is that together these actions address the entire lifecycle of keeping an engine reliable: inspections identify wear and faults, parts replacement prevents imminent failures, repairs fix defects that arise, and overhaul restores performance and extends life.

The other options describe important tasks but are incomplete. Testing alone doesn’t encompass ongoing upkeep or restoration. Calibration and alignment are specific procedures within maintenance but don’t represent the whole scope. Lubrication and cleaning are routine care activities, but by themselves they don’t capture the full range of maintenance actions.