What describes the relationship between the angles in a right triangle?

In a right triangle, one angle measures exactly 90 degrees, which is the defining feature of this type of triangle. The sum of the angles in any triangle, including right triangles, is always 180 degrees. This fundamental principle of triangle geometry applies universally regardless of the triangle's type (right, acute, or obtuse). Therefore, even though one of the angles is 90 degrees, the remaining two angles must also sum up to 90 degrees to ensure that the total equals 180 degrees. This is why the correct choice describes the relationship accurately.