Answer: Last option.
Explanation:
By definition, a pyramid has a base (which is a polygon) and three or more triangular faces.
You can observe in the image that the the figure has three triangular faces and a triangular base. The sides of the base are all equal, then it is an equilateral triangle.
Then, since the base of the tringular pyramid is an equilateral triangle, the faces are also equilateral triangles.
Therefore, the three-dimensional figure that can be made from the net shown, is:
A triangular pyramid that must have 4 congruent and equilateral triangles.