Telomerase enables unlimited cell division in cancer

Steps:

• Telomerase adds telomeres to chromosome ends, countering shortening during DNA replication.
• Somatic cells have low telomerase, leading to telomere erosion and limited divisions (Hayflick limit).
• Stem and cancer cells express high telomerase, allowing persistent division.
• Evaluate statements: A misattributes damage to telomerase; B inverts stem cell telomerase levels; C correctly states somatic limits but overlooks cancer context; D links high telomerase to tumor proliferation.

Why D is correct:

• High telomerase in cancer cells maintains telomeres, enabling immortalization and sustained tumor growth per the telomere hypothesis of cellular aging.

Why the others are wrong:

• A: Telomerase protects genes by preserving telomeres, not damaging them.
• B: Stem cells have high telomerase, supporting extensive divisions, not low.
• C: Accurate for body cells but incomplete; question seeks broadest correct statement on telomerase function.

Final answer: D