A metal wire of length l and radius r is fixed between rigid supports. Initially it is just taut. Now, due to decrease in temperature, the tension developed in the wire

• A

  $\propto \mathrm{l}$

• B

  $\propto \frac{1}{\mathrm{l}}$

• C

  $\propto {\mathrm{r}}^2$

• D

  $\propto \frac{1}{{\mathrm{r}}^2}$