The Number of Technological Civilizations in Our Galaxy Is Limited

question 87

Multiple Choice

The number of technological civilizations in our galaxy is limited by

• A)the number of stars in our galaxy.
• B)the fraction of stars with planets.
• C)the number of planets per star in habitable zones longer than a few billion years.
• D)the fraction of suitable planets where technical life forms evolve.
• E)the number of stars in our galaxy, the fraction of stars with planets, the number of planets per star in habitable zones longer than a few billion years, and the fraction of suitable planets where technical life forms evolve.

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Definitions:

Instinct

An ingrained behavior observed in animals that consistently occurs in reaction to designated stimuli.

Drive-Reduction Theory

A psychological theory suggesting that motivation arises from biological needs driving an individual to act in ways that reduce drives and achieve homeostasis.

Physiological Needs

The most basic human necessities required to sustain life, such as air, water, food, shelter, and sleep, according to Maslow's hierarchy of needs.

Psychological Wants

Desires primarily based on emotional or mental fulfillment rather than basic survival or physiological needs.