A Wire of Circular Cross Section of Diameter D and Length

Multiple Choice

A wire of circular cross section of diameter d and length L is stretched an amount $\Delta$ L by a steady force F.An equal force would produce how much stretch in a similar wire of diameter 2d and length 2L?

A) $\Delta$ L/8
B) $\Delta$ L/4
C) $\Delta$ L/2
D) 2 $\Delta$ L
E) 4 $\Delta$ L