A Major Threat to Validity to the Posttest-Only Design with Nonequivalent

question 57

Multiple Choice

A major threat to validity to the posttest-only design with nonequivalent groups is:

• A) History
• B) Testing
• C) Instrumentation
• D) Differential selection

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Definitions:

Worm Gear

Spiraled single-groove shaft gear.

Hourglass Shape

Describes an object or figure with a narrow middle section flanked by wider top and bottom sections, resembling the shape of an hourglass.

Over-center Operation

A mechanical principle where a lever or mechanism goes beyond the center point of its range, achieving a locked or stable position.

Air Power Steering

A type of power steering system that uses compressed air to reduce the force needed to steer the vehicle, enhancing maneuverability.