Which of the following is accurate?

a. the reason that researchers use probability samples is because they guarantee representativeness of the sample
b. in general, the more heterogeneous a population, the smaller the sample needed for representativeness
c. a simple random sample is appropriate when the researcher wants to over-represent a characteristic in the population
d. a sample is representative of the population from which it is drawn if the aggregate characteristics of the sample approximate those of the general population

The affirmation accurated is:

d. A sample is representative of the population from which it is drawn if the aggregate characteristics of the sample approximate those of the general population.

Explanation:

When is taken a sample from a population, in change of taken all them, regularly must be because the population is enough big and the analysis of that could be too extensive or expensive, but when the sample is taken, this must show the characteristics of the total population, in contrary case, it could not be named "representative", because although the investigator realizes the analysis, this won't be applied to the original population.

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