Answer:
d. credit to purchases.
Step-by-step explanation:
With Periodic Method, Inventory Valuation is done at financial year end.
When Buyer Purchases Merchandise the entries will be :
Purchases (debit)
Trade Payable (credit)
When Buyer Returns Merchandise, the entries will be :
Trade Payable (debit)
Purchases Returns (credit)
Thus a Purchases Return lowers the Purchases amount, so in other words, the Purchases Account is Credited.