Placebos Are Used in Experiments to

question 29

Multiple Choice

Placebos are used in experiments to

• A)control for the variability of individuals who tend to volunteer for research studies.
• B)control for the expectations of some research participants that they will improve just because they are in a research study.
• C)help determine whether an independent variable actually causes a statistically significant change in a dependent variable.
• D)make certain that the treatment and control group are randomly selected.

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Definitions:

Sedimentary Rock

A type of rock that forms from the accumulation and cementation of mineral and organic particles, often in layered deposits.

Magma

Molten rock located beneath the surface of the Earth, which can form intrusive or extrusive igneous rocks upon cooling.

Metamorphic Rock

Rock that has undergone transformation in texture, mineralogy, or chemical composition due to high temperature and pressure.

Partial Melting

The process by which only a portion of a solid is melted, often occurring in the Earth's mantle, leading to the generation of magma.