Write 'True' or 'False' and justify your answer.
If the length of the shadow of a tower is increasing,then the angle of elevation of the sun is also increasing.

(B) False.
Let the height of the tower be $h$ and the length of the shadow be $x$. The angle of elevation of the sun is $\theta$. In the right-angled triangle formed by the tower and its shadow,we have $\tan(\theta) = \frac{h}{x}$.
As the length of the shadow $x$ increases,the value of the fraction $\frac{h}{x}$ decreases. Since $\tan(\theta)$ is an increasing function for $0^\circ < \theta < 90^\circ$,a decrease in $\tan(\theta)$ implies a decrease in the angle $\theta$. Therefore,as the shadow length increases,the angle of elevation of the sun decreases.