Answer: B. The perpendicular bisectors for each side are the only lines of reflection.
Explanation:
A reflectional symmetry or line of symmetry divides a figure into two mirror-image equal halves.
For regular polygon with n sides, it has n line of symmetry.
If n is even then the lines that connect pairs of opposite vertices are lines of reflection.
If n is odd then the lines which passes through a vertex point and the mid point of the side opposite to it is the line of symmetry, and that lines are perpendicular bisector for side opposite to the vertex.
Thus, if n is odd then the perpendicular bisectors for each side are the only lines of reflection.