Robert left from a Pvt Company. Management hold his salary Rs. 15000/- for one month. Earlier Robert borrowed Rs. 7280/- from company. But Robert forget that. After one month Robert asked his salary and accountant gives Rs.18500/- to him. What is the incentive amount given to Robert? Choose the correct choice:
A) 9500  B) 12500  C) 10780  D) 10500  E) 8600

Rationale: "total salary = rs . 15000 / - borrowed money = 7280 / - balance salary = 15000 - 7280 = 7720 paid amount = 18500 / - incentive amount = 18500 - 7720 = 10780 / - answer is c"
Answer: C