It Is Believed That HIV Has Passed from Chimps to Humans

question 27

Multiple Choice

It is believed that HIV has passed from chimps to humans more than once. This is very telling since it suggests that animal- to- human viral transmissions may be more common than previously thought. What is the best evidence in support of the conclusion that HIV made the chimp- to- human leap more than once?

• A) HIV has appeared on multiple continents.
• B) Human- to- human transmission of HIV requires direct personal contact that simply could not have resulted in the widespread outbreak we see today.
• C) Several species are known to have similar viruses resulting in immunodeficiency diseases.
• D) HIV has multiple strains, and the virus does not appear to be able to leap from humans back to chimps.

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Definitions:

Real GDP

The calculation of a nation's economic production after accounting for changes in prices, such as inflation or deflation, which shows the actual value of the products and services generated.

Nominal GDP

The gross domestic product measured in current prices, without adjusting for inflation, representing the value of all goods and services produced within a country's borders in a specific time period.

Real GDP

The measure of a nation's gross domestic product adjusted for inflation, showing the value of goods and services produced in real terms.

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Earthmoving equipment consists of heavy-duty vehicles designed for construction tasks, especially ones involving earthwork operations.