A metal wire of length $L$, area of cross-section $\mathrm{A}$, and Young's modulus $Y$ is stretched by a variable force $F$ such that $F$ is always slightly greater than the elastic forces of resistance in the wire. When the elongation of the wire is $\ell$
(A) The work done by $F$ is $\frac{Y A \ell^{2}}{2 L}$
(B) The work done by $F$ is $\frac{Y A \ell^{2}}{L}$
(C) The elastic potential energy stored in the wire is $\frac{Y A \ell^{2}}{2 L}$
(D) No heat is produced during the elongation