Option A is correct
Explanation:Pythagorean Theorem only work for right angle triangles.
Hence, the option Pythagorean Theorem works for all triangles is wrong
The Pythagorean Theorem is used to find missing sides of right angle triangles.
The option The Pythagorean Theorem is used to find missing angles is wrong
The longest side in a right triangle is called the hypotenuse.
This is correct
Option A is correct