What did the miller-urey experiment demonstrate?

earth's early atmosphere contained abundant oxygen.
early earth was constantly bombarded with comets.
small organic molecules formed from gas mixture of earth's early atmosphere.
organisms were spontaneously generated on early earth.

 Option D

Miller-Urey experiment indicates that the Organisms were suddenly generated on early Earth.

Explanation:

According to the Miller-Urey experiment in the early days of the earth the organisms were generated suddenly on the earth surface.  

Some organic compounds are formed on the earth from the simple compounds at the some special conditions.

Because for any organism to generate some particular conditions are required. So the above experiment proved that many organisms are created automatically on the early days of earth .