Which of these is an example of multi-stage sampling? a.)

Dividing the total population of Florida into groups and then selecting households in proportion from these groups.

b.)

Dividing the population of Florida into groups and then making simple random samples of those groups.

c.)

Choosing Florida as a sample, then selecting a sample of school districts within Florida, then sampling the number of children in households living in those areas.

d.)

Randomly selecting households from the entire population of Florida.