A hallmark cancer cell characteristic includes which of the following?

• A. Genetic instability, abnormal rapid growth, undifferentiated cells
• B. Stable genome, slow growth, fully differentiated cells
• C. Normal telomere maintenance and apoptosis
• D. Limited replication with strict contact inhibition

Answer: (C)

Genetic instability driving uncontrolled growth and a less differentiated state is a classic hallmark of cancer cells. When cells accumulate genomic changes, they can acquire new abilities that promote rapid, unregulated proliferation and a loss of normal differentiation, leading to the malignant phenotype. The option that lists genetic instability along with abnormal rapid growth and undifferentiated cells lines up with these fundamental cancer traits.

The other descriptions describe normal cell behavior: a stable genome with slow growth and full differentiation reflects healthy, mature cells; limited replication with strict contact inhibition describes how normal cells respect tissue boundaries; and normal telomere maintenance with apoptosis would limit uncontrolled growth and isn’t what cancer cells typically exhibit (many cancers maintain telomeres to achieve replicative immortality and resist apoptosis).