Which of the Following Statements Is Incorrect

Which of the following statements is incorrect?

A) The expected value of a discrete probability distribution is the long-run average value assuming the experiment will be repeated many times.
B) The standard deviation of a discrete probability distribution measures the average deviation of the random variable from the mean.
C) The distribution is considered uniform if all the probabilities are equal.
D) The mean of the probability distribution is equal to the square root of the variance.