A bank customer borrowed $10,000, but received y dollars les

GMAT weekly questions

A bank customer borrowed $10,000, but received y dollars less than this due to discounting. If there was a separate $25 service charge, then, in terms of y, the service charge was what fraction of the amount that the customer received?

A. 25/(10,000 - y)
B. 25/(10,000 - 25y)
C. 25y/(10,000 - y)
D. (y - 25)/(10,000 - y)
E. 25/(10,000 - (y - 25))