Coaxial Cable a Has Twice the Length,twice the Radius of the Inner

Multiple Choice

Coaxial Cable A has twice the length,twice the radius of the inner solid conductor,and twice the radius of the outer cylindrical conducting shell of coaxial Cable B.What is the ratio of the inductance of Cable A to that of Cable B?

A) $4 \ln 2$
B) $2 \ln 2$
C) 2
D) $2 \ln 4$
E) $4 \ln 4$