Answer:B
Step-by-step explanation:
Given
Height of building [tex]h=30\ m[/tex]
Angle of depression [tex]\theta =45^{\circ}[/tex]
Suppose distance of Point A from base of building be [tex]x[/tex]
From diagram we can write
[tex]\Rightarrow \tan \theta =\dfrac{h}{x}[/tex]
[tex]\Rightarrow \tan (45^{\circ})=\dfrac{30}{x}[/tex]
[tex]\Rightarrow 1=\dfrac{30}{x}[/tex]
[tex]\Rightarrow x=30\ m[/tex]
So, point A is [tex]30\ m[/tex] from base of building