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❓ 题目 According to the passage, what is the primary reason the hydra can achieve biological immortality?

A. A) It possesses a unique genetic mutation that halts all cellular aging.
B. B) Its interstitial stem cells continuously replace differentiated cells, preventing damage accumulation.
C. C) It has no predators or diseases in its natural environment.
D. D) Its stem cells remain quiescent permanently, avoiding replication errors.

B) Its interstitial stem cells continuously replace differentiated cells, preventing damage accumulation.