Which statement about combination locks is true?

• A. A combination lock is only portable.
• B. A combination lock cannot be a built-in lock.
• C. A combination lock can be a built-in lock or a padlock.
• D. A combination lock is always digital.

Answer: (C)

Combination locks come in different forms, so they aren’t limited to one style. A lock that uses a sequence of numbers or symbols can be implemented as a padlock you carry or as a built‑in lock integrated into a door, safe, or piece of luggage. That versatility is why the statement that a combination lock can be a built‑in lock or a padlock is true. It captures the idea that these locks aren’t restricted to a single form.

It’s not just portable, since built‑in versions exist. And it isn’t necessarily digital, because many combination locks are mechanical dDial or lever types.