Answer:
supplies expense  800 debit
       supplies        800 credit
--to record year-end adjustment on supplies used--
Explanation:
we will adjust for the amount of supplies consumed over the period:
1,200 beginning - 400 ending = 800 consumed.
We are going to decrease the assets account supplies and recognize na expense account to represent the use of the supplies.
The assets will be credited as is decreasing and the expense debit to make debit = credit