The Letter $\alpha$ In the Formula for Constructing a Confidence Interval Estimate of Interval

Multiple Choice

The letter $\alpha$ in the formula for constructing a confidence interval estimate of the population mean is:

A) the level of confidence.
B) the probability that a particular confidence interval will contain the population mean.
C) the area in the lower tail of the sampling distribution of the sample mean.
D) None of these choices.