If a Test of Hypothesis Has a Type I Error

Multiple Choice

If a test of hypothesis has a Type I error probability of .05,this means that:

A) if the null hypothesis is true,we don't reject if 5% of the time.
B) if the null hypothesis is true,we reject it 5% of the time.
C) if the null hypothesis is false,we don't reject it 5% of the time.
D) if the null hypothesis is false,we reject it 5% of the time.