Finds fault with choices by fool (8)
I believe the answer is:
nitpicks
'finds fault' is the definition.
(I've seen this before)
'choices by fool' is the wordplay.
'choices' becomes 'picks' ('pick' can be a synonym of 'choice').
'by' says to put letters next to each other.
'fool' becomes 'nit' (I've seen this before).
'picks' put after 'nit' is 'NITPICKS'.
'with' acts as a link.
(Other definitions for nitpicks that I've seen before include "Quibbles" , "Finds fault" , "Finds petty faults" .)