A. Is the answer
The Hardrock Mining and Reclamation Act (H.R. 2262), instituted royalty payments for minerals taken from public lands, established modern environmental standards and bonding requirements for mine operations and accelerated cleanup of abandoned mines.
The answer would be Prevent yourself from knowing what was in the pill bottles, and distributed the bottles randomly to the subjects
When researcher know which group got the treatment and which group got placebo, they might be biased. It will be better if the researcher is "blinded" and ask third party to help labeling the drug. The drug should be distributed randomly to makes the subject in control and treatment group as similar as possible.
