Answer:
The correct option is C. 50 feet.
Therefore the girl is 50 feet away from the tree.
Explanation:
Consider a Right angle Triangle
Elevation to the tree is ' θ '
Adjacent Side to θ = distance from the tree to girl = distance
Opposite Side to θ = height of the tree = height

To Find:
distance from the tree to girl = distance
Solution:
In Right angle Triangle Tangent Identity

Substituting we get


........Given
Comparing the given equation with the above we get

Therefore the girl is 50 feet away from the tree.