The rate of a certain chemical reaction is directly proportional to the

square of the concentration of chemical A present and inversely proportional

to the concentration of the chemical B present . If the concentration of

chemical B is increased by 100 persent, which of the following is closest to

the percent change in the concentration of chemical of A required to keep

the reaction rate unchanged?

A 100% increase

B 50% decrease

C 40% decrease

D 40 % increase

E 50% increase