Which of the Following Is True of the OLS T

Which of the following is true of the OLS t statistics?

A) The heteroskedasticity-robust t statistics are justified only if the sample size is large.
B) The heteroskedasticty-robust t statistics are justified only if the sample size is small.
C) The usual t statistics do not have exact t distributions if the sample size is large.
D) In the presence of homoscedasticity,the usual t statistics do not have exact t distributions if the sample size is small.