A salesman's terms were changed from a flat commission of 5% on all his sales to a fixed salary of Rs. 1,000 plus 2.5 % commission on all sales exceeding Rs. 4,000. If his remuneration as per the new scheme was Rs. 600 more than by the first scheme, what were his sales worth

• A. Rs. 11, 000
• B. Rs. 17, 000
• C. Rs. 16, 000
• D. Rs. 12, 000