Selection Is a Threat to the Internal Validity of Which

question 13

Multiple Choice

Selection is a threat to the internal validity of which of the following designs?

• A) Nonequivalent comparison group design
• B) Interrupted time-series design
• C) Regression-discontinuity design
• D)All of the above

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Definitions:

Mesodermal Tissue

The middle layer of the three primary germ layers in an embryo that develops into connective tissue, blood, muscle, and internal organs.

Chelicerae

Paired appendages near the mouth of arachnids, such as spiders and scorpions, used for feeding.

Spiders

Arachnids characterized by eight legs, chelicerae with fangs that inject venom, and the ability to produce silk, often used to make webs for catching prey.

Subduing Prey

The act of overpowering or bringing under control an organism intended as food by a predator.