Correct Option: C
Let us draw the figure from the given question.
Let, T be the top of the tower AT. Let, AT = h m. Let, AB and AC be the shadows of the tower when the sun’s altitude is 60° and 30°, respectively.
Then, BC = 50m. Let, AB = x m.
| In figure TBA , cot 60° = | AB |
| AT |
| ⇒ | x | = | cot60° | ⇒ | x = | h | | ........(1) |
| h | √3 |
∴ AC = AB + AC = 50 + h
| In figure TCA , cot 30° = | AC |
| AT |
| ⇒ | x + 50 | = | cot30° | ⇒ | x + 50 | = | √3 h | | .......( 2 ) |
| h |
Subtracting Equation (1) from Equation (2),
| 50 | = |  | √3 - | 1 |
 | h | ⇒ | h = 25 √3 m. |
| √3 |
Hence , the height of the tower is 25 √
3 m.
