Find the two dimensional cross-section could be obtained after slicing a cube?

Hint: When we are moving from three dimensional shape to two dimensional then either you can go with the projection of the shape or when the question is about slicing or cutting then you have check with the detail how are cutting the given shape like in this question it is given that the shape is going to be sliced, and slicing is done perpendicularly.

Complete step-by-step answer:
Here in the question we are given this statement that the cross-section which we are going to obtain is two dimensional hence the required shape is square but if this statement was not present there then the possible answers could be square or cuboids, or any other shape as per the direction given in question.
The given shape in the question is a cube, and we know that the cube has the same length as each side, so we can draw the shape and see what comes after slicing.

After slicing the shape keeping in mind that we have to obtain a two dimensional image, we obtain:

This is a square, and having all sides equal and every adjacent angle is ninety degrees.


Note: While doing the cross-section you have to be clear that the original dimension of the question object will not change, if the slicing is done perpendicularly, now the thickness of the slice will determine the object coming after slicing is two dimensional or three dimensional.