单项选择题
A．was interested in flowers and insects in his childhood B．lost his hearing when he was a child C．didn't like his brothers and sisters D．was born to a naturalist's family
A．full of ambition B．knowledgeable C．full of enthusiasm D．self-disciplined
A．has a great deal of trouble doing mental arithmetic B．lacks some of the qualities required of a scientist C．just reads about other people's observations and discoveries D．comes up with solutions in a most natural way