Research studies conducted by those in professional disciplines fall into several categories. which of these is concerned with the distribution and determinants of health, diseases, and injuries in human populations? a. clinical researchb. basic science researchc. epidemiological researchd. health services research

c. Epidemiological research

Explanation:

Epidemiological research -

The term Epidemiology , refers to the study involving the study of diseases over the wholesome area of population of a specific organism , which could be humans or animals , involving the cause , effect and symptoms of the disease .

The people doing  Epidemiological research , find the factors which can lead to the disease and the factors to help people fight against the disease  .

The disease could be smallpox , as it can spread from person - to - person and hence is a cause of concern .

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