Concept:A regular polygon with n sides has exactly n lines of symmetry.Explanation:Check each option.Option A: A regular polygon with 10 sides has 10 lines of symmetry. This is true because each line passes through a vertex and the midpoint of the opposite side.Option B: A circle has infinitely many lines of symmetry, not none. So false.Option C: An angle has only one line of symmetry, which is its bisector. So false.Option D: A regular hexagon has 6 lines of symmetry, not 4. So false.Hence only option A is correct.
