Answer:
Option B
Explanation:
Remember these facts about the following options:
An acute angle is less than 90 degrees.
A right angle is exactly 90 degrees.
A straight angle is more or less a straight line.
An obtuse angle is an angle greater than 90 degrees.
One of the most notable factors of a right angle is the fact that it takes the shape of an L, speaking of how the photo given takes the shape of an L we can immediately exclude options A, B, and D and say option B or
"right" is our answer.
Hope this helps.