What causes the free surface of a liquid to have minimum area?

If the work done in increasing the size of a soap film from $10\;cm \times 6\;cm$ to $10\;cm \times 11\;cm$ is $2 \times 10^{-4}\;J$,then the surface tension is:

In most liquids,with a rise in temperature,the surface tension of a liquid

With an increase in temperature,surface tension of liquid (except molten copper and cadmium)

What tendency do molecules on the surface of a liquid possess?

What mass should be suspended from the wire $CD$ to keep it in equilibrium?