What is the central scientific puzzle presented by comparing skin cancer rates in Australia and Brazil?

Brazil has a surprisingly low skin cancer rate for a country with a large population.

Australia has a much higher skin cancer rate than Brazil, despite both countries receiving comparable amounts of sunlight.

The amount of sunlight is the only factor determining a country's skin cancer rate.

Skin cancer is more dangerous in the Southern Hemisphere than in the Northern Hemisphere.

In the scientific investigation of skin cancer rates, why is Brazil a useful country to compare with Australia?

Because Brazil and Australia are both located in the Southern Hemisphere.

Because Brazil has a much larger population, making the statistical comparison more dramatic.

Because its similar level of sun exposure helps to control for that variable, pointing to other potential causes.

Because Brazil's low cancer rate proves that sunlight exposure is not a significant health risk.

Sunlight exposure is not a factor in the development of skin cancer.

Other factors besides the total amount of sunlight contribute to Australia's high skin cancer rate.

Australians must spend significantly more time outdoors than Brazilians do.

The methods for diagnosing skin cancer in Brazil are less advanced than in Australia.

A country's skin cancer rate is determined solely by the amount of sunlight it receives.

Genetic factors can play a role in an individual's risk for developing skin cancer.

Public health campaigns can effectively reduce rates of preventable diseases.

Skin cancer is a serious global health issue that requires further study.

Look for other differing factors, like local industries or allergens.

Conclude the difference is purely due to genetics.

Assume air quality is the only possible cause.

Immediately copy the public health policies from Town B to Town A.