The Reduced Use of Heroin by Soldiers After the Vietnam

question 17

Multiple Choice

The reduced use of heroin by soldiers after the Vietnam War can be explained by:

• A)returning to their former lives reduced the psychological need for heroin
• B)unavailability of pure or high-grade heroin in the U.S.
• C)both a & b
• D)None of the above

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Definitions:

Directional Selection

A mode of natural selection where individuals with traits on one end of the spectrum are more likely to survive and reproduce, causing a shift in the population's genetic makeup.

Tree-Dwelling Frog

Amphibians that spend a significant portion of their lives in trees, exhibiting adaptations such as suction cup-like toe pads to aid in climbing.

Heritable Characteristic

A trait that can be passed from parents to their offspring through genes.

Quantifiable

Capable of being measured or expressed as a numerical value.