Answer: The correct option is (B) octagon.
Step-by-step explanation: Given that an interior angle of a regular polygon has a measure of 135°.
We are to select the type of the polygon from the given options.
We know that, if n represents the number of sides of a regular polygon and α be its exterior angle, then
![n=\dfrac{360^\circ}{\alpha}.](https://tex.z-dn.net/?f=n%3D%5Cdfrac%7B360%5E%5Ccirc%7D%7B%5Calpha%7D.)
Given that,
an interior angle of the regular polygon is 135°.
So, the measure of an exterior angle will be
![\alpha=180^\circ-135^\circ=45^\circ.](https://tex.z-dn.net/?f=%5Calpha%3D180%5E%5Ccirc-135%5E%5Ccirc%3D45%5E%5Ccirc.)
Therefore, the number of sides of the regular polygon is
![n=\dfrac{360^\circ}{\alpha}=\dfrac{360^\circ}{45^\circ}=8.](https://tex.z-dn.net/?f=n%3D%5Cdfrac%7B360%5E%5Ccirc%7D%7B%5Calpha%7D%3D%5Cdfrac%7B360%5E%5Ccirc%7D%7B45%5E%5Ccirc%7D%3D8.)
So, there are 8 sides of the polygon and hence it is an OCTAGON.
Thus, (B) is the correct option.