Answer:
D. The samples are independent because there is not a natural pairing between the two samples
explanation:
Independent samples do not affect each other as each group is selected randomly. They are common in statistical analysis, example: when there is a control group and an experimental group and the subjects for each group are different. In the above example, the samples do not depend on each other. There are 90 randomly selected married men in one group and 90 randomly selected married women in the other. The subjects are different in the two groups and so they do not affect each other. This is unlike dependent/paired samples where for example same subjects are used before and after a medication and therefore each group affects the other.
