Respuesta :
Answer:
Option A. a straight line.
Step-by-step explanation:
As we know sum of the interior angles of a triangle is equal = 180°
Therefore for option A.
All angles on a straight line is equal to 180°.
Fro option B.
Sum of all angles at point is equal = 360° or a circle, which is not equal to 180°. Therefore not the answer.
For option C.
a right angle is equal to 90°. Therefore not the answer.
For option D.
An obtuse angle is greater than 90° but always less than 180°. Therefore not the answer.
