The major factors in glacial periods lasting tens of millions of years appear to be ________.
A. an increase in volcanic activity and excess amount of methane in the atmosphere
B. a long-term cooling of the Sun and extended periods of maximum axial tilt
C. having one or more large continental masses near the poles and oceanic circulation that is more longitudinal (north-south) than latitudinal (east-west)
D. having one or more large continental masses near the equator and extended periods of minimum axial tilt of Earth
E. minimum rates of coral and limestone formation and the existence of a supercontinent
Answer: C
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What will be an ideal response?