Copper of fixed volume 'V' is drawn into wire of length $'\lambda'$. When this wire is subjected to a constant force 'F', the extension produced in the wire is $'\Delta \ell'$ . Which of the following graph is a straight line ?

Question

( A ) $\Delta \ell \; versus \; 1/\ell^2$
( B ) $\Delta \ell \; versus \; \ell$
( C ) $\Delta \ell \; versus \;\ell^2$
( D ) $\Delta \ell \; versus \; 1/\ell$