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According to paragraph 1, researchers are trying to answer which of the following question about gliding species A. Why gliding animals, which are uncommon in most tropical forests, have developed in so many different families in Southeast Asia. B. Why gliding animals developed in many tropical forests in Southeast Asia before they evolved in other tropical forests in the world. C. Why gliding animals limitedly evolved in tropical rain forests. D. Why gliding animals evolved so slowly in the tropical forests of Southeast Asia.