Person arranged extremely sensible answer (8)
I believe the answer is:
response
'answer' is the definition.
(I know that answer can be written as response)
'person arranged extremely sensible' is the wordplay.
'arranged' is an anagram indicator (letters rearranged).
'extremely' says to hollow out the word (remove centre letters) (only the extremes of the word are used).
'sensible' with its middle taken out is 'se'.
'person' is an anagram of 'respon'.
'respon'+'se'='RESPONSE'
(Other definitions for response that I've seen before include "Rejoinder, retort" , "Reply, rejoinder" , "bid by partner" , "Press one for a reply" , "Reaction, reply" .)