Straight and clear about answer (4)
I believe the answer is:
neat
'straight' is the definition.
('neat' can be a synonym of 'straight')
'clear about answer' is the wordplay.
'clear' becomes 'net' (as in net profit).
'about' indicates putting letters inside.
'answer' becomes 'a' (abbreviation eg in Q and A).
'net' placed around 'a' is 'NEAT'.
'and' acts as a link.
(Other definitions for neat that I've seen before include "Tidy and spruce" , "compact" , "avoiding water?" , "Steer - straight - trim" , "Tidy, well-ordered" .)