Answer
B
Work Step by Step
Recall: $\cot\theta=\frac{\text{side adjacent}}{\text{side opposite}}$
Given: $x=5\cot 38^{\circ}$
$\implies \cot 38^{\circ}=\frac{x}{5}$
This implies that the adjacent side to the $38^{\circ}$ angle is $x$ and the opposite side to it is the side with length $5$. This is the case in the right triangle B.
