Answer: D. All interior angles and all sides are congruent.
Explanation:
If it is a regular polygon, then all angles and sides have to be congruent.
The interior angles aren’t congruent to the exterior angles.
Not all angles have to be congruent, in regular or irregular.
Since this polygon has 25 sides, opposite pairs aren’t parallel because there are an odd number of sides. That means there are no opposite pairs.