Pertinent, well-chosen (8)
I believe the answer is:
apposite
This clue is a double definition.
'pertinent' is the first definition.
(I know that pertinent can be written as apposite)
'well-chosen' is the second definition.
(I've seen this before)
(Other definitions for apposite that I've seen before include "Pertinent, well-chosen" , "Appropriate for purpose or occasion" , "Meet" , "Appropriate, pertinent" , "A pit pose could be to the purpose" .)