Which of the Following Is Not an Assumption of Linear

Which of the following is not an assumption of linear regression?

A) Across the entire range of the X-values, the distribution of Y-values is normally distributed around the regression line.
B) Across the entire range of the X-values, the mean of the Y-values lies on a straight line.
C) Across the entire range of the X-values, the number of Y-values is constant.
D) Across the entire range of the X-values, the variance of the Y-values is the same.