Prefer to adopt (6)
I believe the answer is:
choose
I believe this is a double definition.
'prefer' is the first definition.
(synonyms)
'adopt' is the second definition.
(I know that adopt is a more specific form of the action choose)
'to' acts as a link.
(Other definitions for choose that I've seen before include "Vote" , "So echo (anag) - wish" , "Pick, select." , "Make a selection" , "Think fit" .)