To Prevent the Possibility That a Placebo Effect or Researchers

question 134

Multiple Choice

To prevent the possibility that a placebo effect or researchers' expectations will influence a study's results, scientists employ

• A) control groups.
• B) experimental groups.
• C) random assignment.
• D) the double-blind procedure.

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Definitions:

Fovea

A small, central pit in the retina of the eye responsible for sharp central vision, essential for activities where visual detail is of primary importance, like reading and driving.

Receptor Cells

Specialized cells which detect and respond to external or internal stimuli, converting them into signals that can trigger specific responses.

Night Vision

The ability to see in low-light conditions, often enhanced through the use of night vision equipment or naturally adapted vision in some animals.

Rods

Photoreceptor cells in the retina of the eye that are sensitive to low light levels and are important for night vision.