Which of the Following Is NOT a Source of Internal

question 2

Multiple Choice

Which of the following is NOT a source of internal invalidity?

• A) selection bias
• B) external events
• C) contamination
• D) statistical control

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Definitions:

Glucose

An essential energy-supplying sugar, fundamental to living entities and found in a vast array of carbohydrates.

Aerobic Respiration

A process of producing cellular energy involving oxygen. Cells use oxygen to convert glucose into ATP, releasing carbon dioxide and water.

Oxidized

Refers to a substance that has lost electrons and increased its oxidation state, often as part of a chemical reaction involving oxygen.

Reduced

In chemistry, refers to the gain of electrons or decrease in oxidation state by a molecule, atom, or ion.