Answer:
b. increase expenses by $12,900
Explanation:
The final balance of Store Supplies were 19,350, but the actual year-end store supplies inventory were 6,450. That means that from all purchase 12,900 (19,350 – 6450) were used during the accountable year, therefore, those were expenses that should be recognized.
The adjusting entry is: Debit supplies expense for 12,900 and credit supplies for an equal amount.