A Source of Internal (Causal) Invalidity Occurring When the Characteristics

question 19

Multiple Choice

A source of internal (causal) invalidity occurring when the characteristics of experimental and comparison group subjects differ in any way that influences the outcome is ______.

• A) selection bias
• B) endogenous change
• C) exogenous change
• D) regression effect

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Definitions:

Million Years

A unit of time equal to one thousand thousand years, often used to express geological and cosmological time scales.

Definite

Clearly stated, decided, or defined; not vague or ambiguous.

Dietary Challenge

A specific difficulty or obstacle that an individual or group faces in meeting their nutritional needs or preferences.

Savannahs

Grassland ecosystems characterized by scattered trees, found in tropical and subtropical regions, providing habitat for diverse fauna.