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:

Suicide

The act of intentionally causing one's own death, often stemming from factors such as psychological disorders, trauma, or overwhelming stress.

Recreational Drugs

Substances taken for pleasure rather than for medical reasons, often associated with altered states of consciousness and legal issues.

Carbon Monoxide

is a colorless, odorless gas produced by burning carbon-based fuels, which can be hazardous or fatal when inhaled in large quantities.

Firearm

A portable weapon that launches one or more projectiles driven by the explosion or rapid combustion of a propellant.