Which polygon will tessellate a plane?

C) Regular Octagon.

Step-by-step explanation:

First let's see what a tessellation is.

Tessellation is a floor made by regular types of tiles without overlapping and gap.

We cannot use all shape of tiles to tessellate a plane.

We are given Regular pentagon, irregular triangle and regular octagon.

The pentagon has 5 sides, all sides are in the same length. We cannot tessellate a plane using pentagon.

The second figure is a irregular triangle, we cannot make tessellate a plane using irregular shapes.

The third figure is a regular octagon. We can tessellate a plane using a regular octagon.

Therefore, answer is C) Regular Octagon.