You Conduct a Study on a Group of Individuals to Examine

question 82

Multiple Choice

You conduct a study on a group of individuals to examine the role of exercise on depression alleviation. You assign the first 50 people who are motivated to sign up to the experimental group, and the second group of 50 people, who sign up much later, to the control group. After one month, you find that the experimental group (who exercised three times a week on average) is significantly less depressed than the control group (who exercised one time a week on average) . Although you may be tempted to conclude that exercise helps stave off depression, you cannot because of a lack of _____ in your study.

• A) random sampling
• B) random assignment
• C) random surveying
• D) random control

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Definitions:

Montreal Protocol

A global agreement aimed at safeguarding the ozone layer through the gradual elimination of several compounds that contribute to its depletion.

Ozone Destroyers

Chemicals, such as chlorofluorocarbons (CFCs), that break down ozone in the atmosphere.

UV Radiation

Ultraviolet radiation, a form of energy emitted by the sun and artificial sources, known for its ability to damage DNA and cause sunburn.

Upper Layer

The topmost section or stratum of a particular structure or environment, often significant in ecological or atmospheric studies.