Listen again to part of the lecture. Then answ
问题详情
Listen again to part of the lecture. Then answer the question. Why does the professor say this:
A．To stress the mysterious nature of severe immune responses
B．To argue that anaphylaxis is mainly the result of bad luck
C．To point out that scientists disagree over what causes allergies
D．To suggest that people are crazy to eat offending substances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：Listen again to part of the lecture. Then answer the question.
"People don't get anaphylaxis from their first bee sting. The immune cells that produce antibodies ... they ... uh ... they have to be sensitized to the offending substance at least once before they overreact to it the second or third time. We don't understand why some unlucky immune systems go crazy the next time they encounter the same substance."
Why does the professor say this:
"We don't understand why some unlucky immune
systems go crazy the next time they encounter the same substance."
The professor's purpose is to stress the mysterious nature of severe immune responses. Scientists do not understand why some immune systems go crazy, or overreact to an offending substance, while other immune systems do not. (2.3)
