Chromatid count across cell cycle phases

Steps:

• Human diploid cells have 46 chromosomes; each consists of 1 chromatid in G1 (total 46 chromatids).
• DNA replication in S phase creates sister chromatids, doubling to 92 chromatids per cell in G2.
• M phase begins with replicated chromosomes (92 chromatids), which separate during anaphase.
• Thus, chromatids number 92 in M (pre-separation), 46 in G1, and 92 in G2.

Why C is correct:

• C (92, 46, 92) matches the definition of sister chromatids forming in S phase and persisting through G2 and early M until separation.

Why the others are wrong:

• A: Understates M phase (46 instead of 92 chromatids pre-separation).
• B: Overstates G1 phase (92 instead of 46 chromatids, as replication hasn't occurred).
• D: Overstates G1 phase (92 instead of 46 chromatids).

Final answer: C