Payment on a portion of accounts payable will
A.decrease net income
B.not affect stockholder's equity
C. Not affect total assets
D.increase total liabilities

First you need to figure out what the journal entry is to record the transaction.

It is:
Debit Accounts Payable for the amount paid
Credit Cash for the amount paid.

Now you know what the journal entry is, you should be able to figure out what the answer is.