Suppose that a triangle T on a unit sphere has area equal to π/2. Which of the following is necessarily true?

Question

Suppose that a triangle T on a unit sphere has area equal to π/2. Which of the following is necessarily true?

A) Each of its angles are equal to π/2.
B) Its height is π/2 and its base has length 2. 
C) It has a vertex at the North Pole.
D) The sum of its internal angles is 3π/2.

Thanks in advance!

Answer 1

The answer is D), by gauss bonnet, all the others are false.