Correct option is: C) 12
We have the height of the tree is BC = 12 m.
Angle of elevation of the sum is \(\angle\)A = \(45^\circ\)
In right \(\triangle\)ABC,
\(\frac {BC}{AB}\) = tan A = tan \(45^\circ\) = 1
= AB = BC = 12 m
Hence, the length of the shadow of the tree is 12 m.