We want to study the angle of an arc given that the length of the said arc is smaller than the radius of the circle.
The correct option is:
"it is less than pi radians"
A circle of radius R has a circumference:
C = 2*pi*R
An arc defined by an angle θ has a length:
L = θ*R
Now, we know that the length of the arc is smaller than the radius, then we have:
θ*R < R
Dividing both sides by R we get:
θ < 1
So we can see that the correct option is:
"it is less than pi radians"
Because it is smaller than 1.
If you want to learn more, you can read:
https://brainly.com/question/15227228