During 2016, a company wrote off $7,500 in uncollectible accounts receivable. At the end of the year, bad debt expense was estimated using a percent of gross sales. In 2017, the company collected $1,500 from an account that was written off in 2016. Recording this collection would include

a) a decrease to gross receivables.

b) a debit to Retained Earnings.

c) a credit to Allowance for Doubtful Accounts.

d) an increase to net receivables.