为什么A不对呢？我觉得C描述的是Cluster抽样

问题如下：

The best approach for creating a stratified random sample of a population

involves:

选项：

A.

drawing an equal number of simple random samples from each

subpopulation.

B.

selecting every kth member of the population until the desired sample size

is reached.

C.

drawing simple random samples from each subpopulation in sizes proportional

to the relative size of each subpopulation.

解释：

C is correct. Stratified random sampling involves dividing a population into

subpopulations based on one or more classification criteria. Then, simple random

samples are drawn from each subpopulation in sizes proportional to the relative

size of each subpopulation. These samples are then pooled to form a stratified

random sample.