A-A+
In paragraph 7 the author explains the term k
问题详情
In paragraph 7, the author explains the term keratin by
A．identifying it in hair and fingernails
B．comparing it to bird feathers
C．providing a definition in the text
D．describing the way that it looks请帮忙给出正确答案和分析，谢谢！
参考答案
正确答案：A
解析："Feathers are made of keratin, the same protein that forms our hair and fingernails and the scales of reptiles." Choice B is not correct because feathers are made of keratin, not compared with keratin. Choice C is not correct because the author does not refer to the text. Choice D is not correct because the only description is the comparison with hair, fingernails, and scales.
