In an Experiment, Extraneous (Nonmanipulated) Variables Are Controlled By

question 9

Multiple Choice

In an experiment, extraneous (nonmanipulated) variables are controlled by:

• A) having more than one experimenter interact with all subjects in the study
• B) using subjects who are similar to each other in nearly all respects
• C) making all aspects of the procedure identical for all conditions, except for the independent variable manipulation
• D) the assignment of subjects to experimental conditions based on the characteristics of the subjects

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Definitions:

Multiple Sclerosis

A chronic autoimmune disease affecting the central nervous system, leading to various neurological symptoms.

Myelin

A fatty substance that forms a sheath around the axons of many neurons, increasing the speed at which electrical impulses propagate along the nerve cells.

Glial Cells

Non-neuronal cells in the central and peripheral nervous systems that provide support and protection for neurons.

Myelin Sheath

A fatty insulation that may surround the axon of a neuron.