Correct option is D
Explanation-
During the M phase (mitotic phase), especially in prophase and metaphase, chromosomes become:
Highly condensed
Visible under a microscope as distinct structures
This is the only phase when they are clearly distinguishable as individual chromosomes.
So, the correct answer is option d - M phase
Incorrect options-
Option a - G₀ phase:
A resting/non-dividing phase.
Chromosomes are decondensed (not visible individually).
Option b - G₁ phase:
First gap phase of interphase.
Chromatin is uncondensed and spread out.
Chromosomes are not distinctly visible.
Option c - S phase:
DNA synthesis phase where chromosomes are replicated, but not yet visible individually.
Still appear as chromatin.
