We select a systematic sample of size n=10 among a population of size N=400.Among the following statements, which are true?

I. Every person in the population has the same probability of selection: 1/400 II.The variance of the estimated mean can be decreased by ordering the frame according to the variable of interest III. There are exactly 40 different possible samples IV. This sampling method can generate an important bias in presence of a cyclic phenomenon V. The probability of selection for each person is the same as a simple random sample with replacement of size n=10 among a population of size N=400.

Response choices:

• A: I and III only.
• B: II and IV only
• C: IV and V only.
• D: II, III and IV only .
• E: All these statements are true