Approval of choice of commercial? (8)
I believe the answer is:
adoption
'approval' is the definition.
(I know that adoption is a type of approval)
'choice of commercial?' is the wordplay.
I cannot really see how this works, but
'choice' could be 'option' (synonyms) and 'option' is found in the answer.
'commercial?' could be 'ad' (abbreviation for advertisement) and 'ad' is present in the answer.
No letters remain.
This explanation may well be incorrect...
'of' acts as a link.
Can you help me to learn more?
(Other definitions for adoption that I've seen before include "Act of taking as one's own" , "process to select candidate" , "Process of taking on another's child" , "takeover" , "approval" .)