Human lose consciousness if exposed to prolonged accelerations of more than 7g. This is of concern to jet fighter pilots, who may experience centripetal accelerations of this magnitude when making high speed turns. Suppose we would like to decrease the centripetal acceleration of a jet, which of the following changes is the most effective?

A) Decrease the turning radius by a factor of two
B) Decrease the speed by a factor of three
C) Increase the turning radius by a factor of four
D) Increase the speed by a factor of two.