Oversampling is a variant used in which of the following sampling techniques? a. Convenience sampling b. Stratified random sampling c. Cluster sampling d. Simple random sampling

Answer: B. Stratified random sampling

Explanation: Stratified random sampling is used in statistics and is a method by which a sampled population is subdivided into smaller so-called sub populations or else known as strata. These sub-groups within a population are formed on the basis of some commonalities such as education, age or income and the like. Random sampling is then performed within these sub groups. It should be emphasised that stratified sampling is used to identify and distinguish between subgroups after sampling, which is why these sub groups are formed on the basis of some common criteria. Therefore, in this sampling method, all members of the population are treated not equally but according to the subgroups formed on the basis of the aforementioned criteria and this is the difference between this sampling and simple random sampling where all members of the population are treated equally. In stratified random sampling, each sub-group within the entire population can be sampled completely independently because such groups are different.