44. Which characteristic represents a derived feature that most clearly distinguishes extant birds from other living reptiles?
(A) Presence of keratinized epidermal structures
(B) Production of shelled amniotic eggs
(C) Maintenance of elevated metabolic temperature
(D) Use of internal fertilization mechanisms
(E) Modification of forelimbs into feathered wings
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統計: A(0), B(0), C(4), D(0), E(3) #3852898
統計: A(0), B(0), C(4), D(0), E(3) #3852898