4. During a sunny afternoon, the sun suddenly seems much less bright than usual. The daylight
seems much less intense, as if there is a dense
cloud cover, but there are no clouds in the sky.
After about a half hour, everything seems
normal again. Which claim about the temporary
decrease in light can be supported by the
evidence?
A. The moon was passing between the sun and
Earth.
B. An airplane was flying overhead and blocked
the light from the sun.
C. There are variations in the amount of light
produced by the sun.
D. A sudden change in temperature increased
the density of the atmosphere.