Answer: Artifacts
Explanation:
Artifacts are the components that are disrupt the external validity or internal validity of result in any research.Artifacts tend to modify or change the authenticity of participant and equipment involved in research field with their presence.
Impact of artifacts can also be influential to understand the process through observing evidences. They impact evidences, documents,tools, equipment, etc.
Commensalism is the answer to your question
The answer is: b. You are in good health.
When you are in good health, the insurance company would see you as a low-risk investment since it you are less likely to become ill and make them pay coverage for the treatment. This would make your insurance payment become substantially less compared to non-healthy or older people.
The Inca were not pre-columbian