Chromosomes visible as two chromatids in prophase Steps:

• Identify stage: prophase, where chromosomes condense into visible two-chromatid structures.
• Count prophase cells: 73.
• Total cells observed: 896.
• Compute percentage: (73 / 896) × 100 ≈ 8%. Why B is correct:
• Prophase features chromosomes appearing as two sister chromatids joined at the centromere, per mitotic stages. Why the others are wrong:
• A. 7%: Underestimates prophase calculation (actual ≈8%).
• C. 9%: Overestimates if mistakenly including metaphase (73+16=89/896≈10%).
• D. 97%: Approximates interphase cells, where chromosomes are not visible as two chromatids. Final answer: B