The Balance in Accounts Receivable at the Beginning of the Year

The balance in Accounts Receivable at the beginning of the year amounted to $16,000.During the year,$64,000 of credit sales were made to customers.If the ending balance in Accounts Receivable amounted to $10,000,and uncollectible accounts expense amounted to $4,000,what is the amount of cash inflow from customers that would appear in the operating activities section of the cash flow statement?

A) $66,000.
B) $64,000.
C) $80,000.
D) None of these answers are correct.