Samples must be representative of the population. A. Therefore, you have to make sure you sample the exact same percent of all subgroups like the exact same percent of boys as in the population and the same number of girls in the population. 2. representative of the population. Therefore, convenience sampling is the best sampling method. 3. representative of the population. Therefore, random sampling is the best sampling method. 4. representative of the population. Therefore, systematic sampling is the best sampling method