Synonym of SECURE

Answer: Option C

Secret : not known or seen or not meant to be known or seen by others.
Comfortable : (especially of clothes or furnishings) providing physical ease and relaxation.
Safe : protected from or not exposed to danger or risk; not likely to be harmed or lost.
Independent : free from outside control; not subject to another's authority.
Secure : fixed or fastened so as not to give way, become loose, or be lost.

Synonym of Secure is Safe