Answer:
D.
Explanation:
The choices to this question are
a.) 1/tan(90-A)
b.) 1/sin A
c.) 1/cos(90-A)
d.) 1/tan A
We know that
, which is a trigonometric identity.
If
then,

But,
and

So,

Which is the inverse of tangent, so

Therefore, the right answer is D.