Which of the Following Is Correct About Cluster Sample

Which of the following is correct about cluster sample?

A) Every member of the population has a known and equal chance of selection.
B) The population is divided into mutually exclusive groups (such as gender or age) ,then random samples are drawn from each group.
C) The population is divided into mutually exclusive groups (such as geographic areas) ,then a random sample of groups is selected.
D) A list of the population is obtained-for example,all persons with a checking account at XYZ Bank-and a skip interval is obtained by dividing the sample size by the population size.