An aging of a company's accounts receivable indicates that $9100 are estimated to be uncollectible. If Allowance for Doubtful Accounts has a $5200 credit balance, the adjustment to record bad debts for the period will require a

credit to Allowance for Doubtful Accounts for $9100.

debit to Bad Debt Expense for $3900.

debit to Bad Debt Expense for $9100.

debit to Allowance for Doubtful Accounts for $3900.