For Young's double slit experiment, two statements are given below....

Statement I is based on the principle of conservation of energy. In an interference pattern, the energy missing at dark fringes appears at the bright fringes. Thus, energy is only redistributed and not destroyed. Statement I is true.

The fringe width in Young's double slit experiment is given by $\beta = \dfrac{\lambda D}{d}$.

Since frequency $\nu = \dfrac{c}{\lambda}$, we have $\beta = \dfrac{c D}{\nu d}$.

This shows that fringe width is inversely proportional to the frequency of light. Therefore, as frequency increases, fringe width decreases. Statement II is false.

Hence, Statement I is true but Statement II is false.

Answer: Statement I is true but statement II is false.