Answer:
d. Both a and b above are correct.
Step-by-step explanation:
In the case when the company unadjusted trial balance reflect a debit balance of allowance for doubtful debts so this represent that the company would have more written off account receivable that would be shown in the beginning balance of the allowance. Also the company should record the bad debt expense as more as the debit balance of the non-adjusted allowance
Hence, the last option is correct