If Done Correctly,stratified Sampling Can Actually Decrease the Standard Error

Multiple Choice

If done correctly,stratified sampling can actually decrease the standard error of the estimator by

A) making sure the strata are more homogeneous on the variables for which statistics will be calculated
B) making sure each strata forms a representative sample of the population
C) decreasing the number of categories within each of the variables for which statistics will be calculated
D) making sure the sample is sufficiently large to ensure a lower sampling error