Kaiden built a grandfather clock using a simple pendulum, but he found that the period was twice as large as as he wanted it to be$.$ In order to halve the period of the pendulum, he can

$$

A$.$

change the mass.

$$

B$.$

halve the length of the string.

$$

C$.$

quarter the length of the string.

$$

D$.$

double the length of the string.

$$

E$.$

quadruple the length of the string.