Which of the following statements about simple random sampling is NOT true?

(A) A. Simple random sampling ensures that each unit in the population has an equal chance of being selected.

(B) B. In simple random sampling with replacement, each selected unit is replaced to the population before the next unit is drawn.

(C) C. Simple random sampling is highly effective when the population is very large and heterogeneous.

(D) D. In a simple random sampling without replacement, a unit is selected, it will never be selected again.