​If length of each side of a cube is doubled, then its volume ____________ the original volume.​

Correct option is C

Given:

If length of cube is double then volume is how much times it's original volume 

Formula Used:

Volume$$(V) = \text{side}^3$$​​

Solution:

Let the original side length of the cube be s.

Then, the original volume is:

​$$V_{\text{original}} = s^3$$​​

If the side length is doubled, the new side length becomes $2s$.

The new volume is:

​$$V_{\text{new}} = (2s)^3 = 8s^3$$

So

$$V_{\text{new}} = 8 \times V_{\text{original}}$$​​

Thus the new volume is 8 times the original volume.