Suit option (4)
I believe the answer is:
vest
'suit option' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for vest that I've seen before include "Upper undergarment, singlet" , "Waistcoat (in USA)" , "An American man's waistcoat" , "Top" , "Undergarment for vets" .)