Answer:
B)
.
Explanation:
We have to find out the reciprocal of
.
We have drawn a triangle for your reference.
In which

AB = opposite side
BC = adjacent side
CA = hypotenuse
Since we know that the
is equal to opposite side upon adjacent side.

Or

Where as the
is equal to adjacent side upon opposite side.
Therefore,

Or

From equation 1 and equation 2 we can say that;

Hence
.