At December 31, before adjusting and closing the accounts had occurred, the Allowance for Doubtful Accounts of Westbury Corporation showed a debit balance of $3,500. An aging of the accounts receivable indicated the amount probably uncollectible to be $2,300. Under these circumstances, a year-end adjusting entry for uncollectible accounts expense would include a:

A) Debit to the Allowance for Doubtful Accounts for $1,200.

B) Credit to the Allowance for Doubtful Accounts for $1,200.

C) Debit to Uncollectible Accounts Expense of $2,300.

D) Debit to Uncollectible Accounts Expense of $5,800.

Explains clearly pls! Why answer is D.