Which evidence provides support for the nebular theory?

AScientists have observed the formation of a distant solar system
BThe Nebular theory has been proven mathematically
CAstronomers have observed protoplanetary disk around distant newborn stars.
DNone of the above

Verified Answer :

The best choice is C.  The evidence that support for the nebular theory is that astronomers have observed protoplanetary disk around distant newborn stars. Also, they saw that planets have the right characteristics to form a disk composed mainly of hydrogen around the Sun.

Answer:

The answer is:

C - Astronomers have observed protoplanetary disks around the distant newborn stars.

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