The Question of Whether the Independent Variable Was the Sole

question 11

Multiple Choice

The question of whether the independent variable was the sole cause of the change in the dependent variable is the basic issue in:

• A) constancy in conditions.
• B) internal validity.
• C) demand characteristics.
• D) external validity.

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Definitions:

Vitamins

Organic compounds that are essential for normal growth and nutrition and are required in small quantities in the diet because they cannot be synthesized by the body.

Minerals

Inorganic nutrients ingested as salts dissolved in food and water.

Free-Living Flatworms

Flatworms that are not parasitic and live independently in various aquatic or moist terrestrial environments.

Pharynx

The membrane-lined cavity behind the nose and mouth, connecting them to the esophagus.