A regular pentagon has how many lines of symmetry?
$
  {\text{A}}{\text{. 3}} \\
  {\text{B}}{\text{. 4}} \\
  {\text{C}}{\text{. 5}} \\
  {\text{D}}{\text{. 6}} \\
$

Hint:In this question we find the result using either the property of polygon or using the geometry. Line of Symmetry: The line of symmetry can be defined as the axis or imaginary line that passes through the centre of the shape or object and divides it into identical halves.

Complete step-by-step answer:
Each regular polygon (equilateral triangle, square, rhombus, regular pentagon, regular hexagon etc.) are symmetry.
The number of lines of symmetry in a regular polygon is equal to the number of sides a regular polygon has.
Geometrically, lines of symmetry can be found by drawing the lines which pass through the centre of the shape or object and divide them into identical halves.
  
From the above figure of a regular pentagon we can see that dashed lines are representing the number of lines of symmetry.
On counting we can find that there are 5 lines of symmetry in a regular pentagon.
Hence, option C .is correct.

Note:-Whenever you get this type of question the key concept of solving this is to know about different shapes and their figures. And remember one thing that lines of symmetry of a regular polygon are equal to the number of sides of that polygon.