Underlying reasons to limit beer supply? (9)
I believe the answer is:
rationale
'underlying reasons' is the definition.
(rationale means the reasoning behind something)
'limit beer supply?' is the wordplay.
'limit' becomes 'ration' (rationing is a kind of limiting).
'beer supply?' becomes 'ale' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'ration'+'ale'='RATIONALE'
'to' is the link.
Can you help me to learn more?
(Other definitions for rationale that I've seen before include "solution in theory" , "Logical basis (for a course of action)" , "justification" , "Good reason" , "Logic, reasoning" .)