If a cancer cell population exhibits increased growth despite checkpoint activation, which mechanism involving receptor tyrosine kinases (RTKs) is most likely driving this resistance to apoptosis?

💡 Explanation

Constitutive RTK activation bypasses normal growth factor signaling requirements because the receptor is always 'on,' triggering downstream pathways promoting cell division and inhibiting apoptosis. Therefore, the cell grows uncontrollably rather than undergoing programmed cell death due to checkpoint activation, making the other options less likely.

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