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The moon's shadow sweeps across the earth's
surface at 1700 km. per hour. This is slightly faster than the speed of
sound (about 1200 km. per hour in air at 0 degrees Centigrade), but much
less than the speed of the moon orbiting about the earth (about 3700 km.
per hour) and much, much less than the speed of light (just shy of 300,000
km. per SECOND!).
Of course, the speed of the Moon's shadow
has nothing to do with sound and its speed of propagation through air at
sea level or atmospheric pressure, other than the fact that they are about
the same speed.
Small wonder then, that at best you have
only a few minutes to view a total solar eclipse.
As for why it wasn't the third answer:
Remember, the earth is also rotating as the moon orbits around it. The
Earth is turning in the same direction as the Moon and the Moon's shadow,
which is from West to East. However, the Moon's shadow is moving faster
than the Earth's surface, and thus it appears to sweep across the Earth
from West to East even faster than the Earth. In this eclipse of February
26, 1998, the shadow will be close to the equator and come from the Pacific
across the Southern Caribbean and into the Atalntic.
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Eclipse Quiz