The following wires $\mathrm{A}, \mathrm{B}, \mathrm{C}, \mathrm{D}$, are made of the same material with diff. length and diameter. Which of these will have the largest extension, when the same tension is applied?
(A) length $=200 \mathrm{~cm}$, diameter $=2 \mathrm{~mm}$
(B) length $=50 \mathrm{~cm}$, diameter $=0.5 \mathrm{~mm}$
(C) length $=300 \mathrm{~cm}$, diameter $=3 \mathrm{~mm}$
(D) length $=100 \mathrm{~cm}$, diameter $=1 \mathrm{~mm}$