Which of the following is NOT a characteristic 特征 of stratified random sampling‏‍‏‍‏A Every possible subset 子集 of the population of the desired 需要的 sample size has an equal chance of being selectedBRa

B. Random sampling is part of the sampling procedure.

Stratified random sampling involves dividing the population into strata based on some characteristic and then randomly selecting individuals from each stratum. Random sampling is not a separate characteristic of stratified random sampling, but rather a necessary component of the sampling procedure as a whole.