Linear regression conditions

In order to run a simple linear regression and then analyze the results statistically when using the least squares approach, certain conditions must be satisfied. Which one of the following statements is NOT one of the conditions that must be satisfied?

a) The distribution of the Yi values must be normally distributed.

b) The distribution of the εi values must be normally distributed.

c) The distribution of the Xi values must be normally distributed

d) The variance σ2 must be constant

e) The εi error terms must be independent or at least uncorrelated among themselves.