What is simple random sampling?

• A. It divides the population into strata.
• B. It selects entire groups.
• C. It relies on convenience sampling.
• D. It gives every member of the population an equal chance of being selected.

Answer: (D)

Simple random sampling means every member of the population has an equal chance of being chosen. This is done by using a random process on a complete list of the population—like assigning numbers and using a random number generator or drawing names—to select the required number of individuals. Because the selection is truly random, there’s no systematic bias toward any particular person or group, so the sample represents the population in expectation. In practice you typically choose without replacement so you don’t pick the same person twice, though some definitions allow sampling with replacement. This approach is what makes simple random sampling distinct from methods like dividing the population into strata or clusters or choosing people because it’s convenient.