Answer:
Step-by-step explanation:
This is simple, the picture that is provided tells us the answer easily.
An angle lower than 90 degrees is called an acute angle. While one that is the same as 90 degrees is a right angle, and one that is more than 90 is obtuse.
We are asked to take a look at angle 4, we can see that is more than 90 degrees. Since 100 is the only answer with an amount higher than 90 degrees and fits the angle, it is the angle.