Larry's Accounts Show the Following for the Year

Larry's accounts show the following for the year:
Net Sales on Account: $200,000
COGS: $150,000
Accounts Receivable at the beginning of the year: $22,500
Accounts Receivable at year end: $17,500
Inventory at the beginning of the year: $45,000
Inventory at the end of the year: $55,000
What is the accounts receivable turnover ratio for the year?

A) 10
B) 4
C) 2.5
D) 5
E) There is not enough information to compute the turnover ratio.