题目内容：
The experimenters thought Washoe was intelligent __________
A．if the Gardeners' argument was sound B．because she was cleverer than other chimps
C．when she wanted to eat
D．while she was at a research center in Ellensburg
E．because she could use sign language to ask for fruits
F．while Washoe was learning sign language
参考答案：
答案解析：