Correct option is D
Given
Letters: X, H, O, A
Formula Used
A line of symmetry divides a figure into two identical halves.
Solution
Letter X has 2 lines of symmetry (horizontal and vertical).
Letter H has 2 lines of symmetry (horizontal and vertical).
Letter O has infinite lines of symmetry (any line through its center).
Letter A has exactly 1 vertical line of symmetry.
So the correct answer is (d)
