The Length of a Certain Wire Is Kept Same While

Multiple Choice

The length of a certain wire is kept same while its radius is doubled. What is the new resistivity of this wire?

A) It is increased by a factor of 4.
B) It is reduced by a factor of 4.
C) It is increased by a factor of 2.
D) It is reduced by a factor of 2.
E) It does not change.