Food Inspectors Need to Estimate the Level of Contaminants in Food

Multiple Choice

Food inspectors need to estimate the level of contaminants in food products packaged at a certain factory. Initial tests were based on a small sample but now the inspectors double the sample size for a follow-up test. The main purpose of the larger sample is to

A) reduce confounding due to other variables.
B) decrease the variability in the population.
C) reduce non-response bias.
D) decrease the standard deviation of the sampling model.
E) reduce response bias.