An airline allowed free baggage only up to 20 kilograms of weight. Each extra kilogram of weight cost a passenger $5 per kilogram. Of the total weight of the baggage that Roger was carrying, 60 percent of the weight was more than the free baggage allowance. If the total ticket cost of Roger including the excess baggage fare was $600, by what percentage did his ticket cost increase because of the excess baggage that he was carrying?

A. 20%
B. 25%
C. 33%
D. 40%
E. 45%

Answer: C

Source: e-GMAT