问题
单项选择题
A Type Ⅰ error:（）
A. rejects a true null hypothesis.
B. rejects a false null hypothesis.
C. fails to reject a false null hypothesis.
答案
参考答案：A
解析：
A Type I Error is defined as rejecting the null hypothesis when it is actually true. The probability of committing a Type I error is the significance level or alpha risk.