Audrey is appointed as a research director at a well-known pharmaceutical company. She is asked to design a set of research studies that will test the effectiveness of the drugs that are being manufactured by the company. To ensure that experimenter bias and research participant bias do not influence the results, Audrey should design a set of

double-blind experiments.

Explanation:

the answer might be either a or c. can't be too sure , because i searched the web, but no valid answers came through.

the historians cited in the article all agree with one another about the cause of the civil war. despite coming from different backgrounds and cultures, the historians agree that slavery was the root cause of the civil war. the fact that all these historiansgenerally agree with one another makes their shared viewpoints more reliable and valid, especially because the historians have different backgrounds and all work for the well-respected institutions of howard university, clemson university, and the university of colorado.