Final answer:
Chromosomes get aligned at the equator of the cell during Metaphase of mitosis, where they are maximally condensed and attached by cohesin proteins, making them easily visible under a microscope. The correct option is B).
Step-by-step explanation:
In which stage of mitosis do chromosomes get aligned at the equator? The answer is B) Metaphase. During this phase of mitosis, all the chromosomes line up along the metaphase plate or the equatorial plane, which is positioned midway between the two poles of the cell.
The sister chromatids at this point are still tightly attached to each other by cohesin proteins, and the chromosomes are maximally condensed, making them highly visible under a microscope.
It is during metaphase that the microtubules are arranged to separate the sister chromatids, pulling one from each pair to opposite sides of the cell. Option B) is the correct one.