Which of the following correctly describes confidence level?
 A. 
 A confidence level is the probability that a simple event will occur.
 B. 
 A confidence level is a value that is added and subtracted from a given value to give an interval where something will likely happen.
 C. 
 A confidence level is the probability that something will fall within a confidence interval.
 D. 
 A confidence level is the probability that something will fall outside of a confidence interval.