The correct option is B cot θ
From Pythagoras theorem, we have
(adjacent side)2+(opposite side)2=(hypotenuse)2
opposite side=√(hypotenuse)2−(adjacent side)2
opposite side=√(cosec θ)2−(1)2
As we know, (cosecθ)2−(1)2=cot2θ
opposite side=√cot2θ
opposite side=cot θ