A-A+
Doctors have discovered a cause of ulcers afte
问题详情
Doctors have discovered a cause of ulcers after many years of experiments.
A. Right
B. Wrong
C. Not mentioned请帮忙给出正确答案和分析，谢谢！
参考答案
正确答案：C
题意：医生们经过多年的实验才发现了造成溃疡的原因。
文章并未提及many years of experiments，故本题选C。
