Which of the Following Is Not an Assumption of the Multiple

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

A) The error terms are independent.
B) The population of error terms has a normal distribution.
C) Populations of error terms observed at different combinations of values of the independent variable (x₁, x₂,. . ., x_k) have equal variances.
D) The level of measurement of the data for the dependent variable is at least ordinal.
E) At any combination of values of x₁, x₂, . . . , x_k, the population of potential error term values has a mean equal to zero.