C. Decrease in allowance for receivables

Explanation:
The credit side of a receivable ledger control account typically includes transactions that decrease accounts receivable. This includes cash received from customers, goods returned by customers (which reduces sales revenue), discounts allowed, and customers’ debts written off. However, a decrease in the allowance for receivables is an adjustment to the provision for doubtful debts, which is not recorded as a credit in the receivable ledger control account. Instead, it impacts the income statement and does not directly affect the receivables balance shown​