TOEFL Listening: ETS-TOEFL听力机经 - M3M61634MOUWV343P$

Why does the professor consider the actual classification of Rafflesia unexpected? A. Its unusual traits are not shared by other plants in its order. B. Its unusual characteristics were not documented until after it was classified. C. Botanists had predicted that no other plants would be related to it. D. Botanists had predicted that it would become extinct before it could be classified.