One study correct if diet's connected (10)
I believe the answer is:
identified
'connected' is the definition.
(identifying is a kind of connecting)
'one study correct if diet's' is the wordplay.
'one' becomes 'i' (Roman numeral).
'study' becomes 'den' (I've seen this before).
'correct' indicates an anagram.
'if'+'diet'='ifdiet'
'ifdiet' anagrammed gives 'tified'.
'i'+'den'+'tified'='IDENTIFIED'
(Other definitions for identified that I've seen before include "Recognised, named" , "Put one's finger on" , "Given name" , "Recognized" , "Pointed out; made known" .)