In a compound microscope, there are two lenses-
1. Objective lens
2. Eyepiece
When we observe any sample in a compound microscope, the magnification depends on the power of both the lenses. The total magnification is the product of the powers of both the lenses. In the options mentioned in the question, the maximum magnification would be in Option D, Objective 10x Ocular 10x.
Here, m = 10 * 10 = 100x.