If We Are Optimistic in Our Assumptions About the Development

Multiple Choice

If we are optimistic in our assumptions about the development of life and intelligence, then the number of technological civilizations currently in the galaxy should equal the

A) average number of planets that produce life.
B) average lifetime of a civilization.
C) average number of planets per star.
D) number of stars in the galaxy's habitable zone.
E) number of stars forming per year.