Which of the Following Is an Example of a Natural

question 7

Multiple Choice

Which of the following is an example of a natural experiment?

• A) A laboratory research on the effectiveness of solar power as an alternative source of fuel
• B) A research on the effectiveness of a new medicine among some voluntary participants
• C) A research on the effect of air pollution on lung disorders by observing the health conditions of people who stay close to industrial areas and those who stay away from industries
• D) A study on the benefits of regular exercise by paying for the membership fees at fitness clubs for one-half of the participants

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Definitions:

Euryarchaeota

A phylum of Archaea, characterized by a diverse range of organisms that include methane producers and salt-loving species.

Hydrothermal Vents

Deep-sea ecosystems found near geothermally heated water emissions, rich in unique life forms adapted to high-pressure, low-light conditions.

Sulfur Springs

Natural springs that emit water containing a high concentration of sulfur and other minerals, often used for therapeutic benefits.

Chemoautotroph

Organisms that obtain energy by the oxidation of inorganic substances, using this energy to synthesize organic molecules from carbon dioxide.