Question

where did scientists look when searching for mutations that protect against malaria?
equatorial regions, because this is where malaria is common
canada, because this country has the best ranked health care in the world
asia, because this content contains the greatest proportion of the worlds population
united states, because this country has the preponderance of medical research money

Explanation:

Malaria is a mosquito - borne disease that thrives in warm, humid climates. Equatorial regions have such climates, making malaria more common there. Scientists would logically look in areas where the disease is prevalent to find protective mutations. Canada has a cooler climate and is not a malaria - endemic area. While Asia has a large population, not all of Asia is malaria - endemic. The United States has limited malaria transmission compared to equatorial regions. So, the most logical place for scientists to look for malaria - protecting mutations is equatorial regions.

Answer:

equatorial regions, because this is where malaria is common