Exhibit 10-10: Identify the Major Threat to Internal Validity in the Following

question 38

Multiple Choice

Exhibit 10-10: Identify the major threat to internal validity in the following research studies.
-Refer to Exhibit 10-10.A teacher researcher randomly assigned students within a classroom to two groups, one of which received some special instructional materials to take home with them to study and to use with homework assignments.The C group did not get the special materials.The researcher was surprised to find that there weren't significant differences between the two groups on achievement tests and other selected measures.

• A) Regression
• B) Diffusion
• C) Mortality
• D) Selection
• E) History

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Definitions:

Trichomoniasis

A sexually transmitted infection caused by the parasite Trichomonas vaginalis, resulting in itching, burning, and often a greenish discharge.

Blood-sucking Insects

Insects that feed on the blood of humans or animals, often acting as vectors for various diseases.

Herpes Simplex 2

A virus that causes genital herpes, characterized by painful blisters and sores in the genital area.

Dysmenorrhea

Painful menstrual cramps that occur just before or during menstruation.