Question

A glass dish containing a few drops of water in the presence of carbon dioxide gas, nitrogen gas, and small organic compounds is heated by a flame and UV radiation. Which early Earth scenario does this set-up most closely resemble?

Answer 1

a. amino acid formation from organic molecules in ocean water splashing on hot rock, sand, or clay
b. deep sea volcanoes giving off gases, sulfur, and iron to produce organic molecules
c. lightning in the early atmosphere, which may have produced the first organic molecules
d. the replication of RNA near the ocean's surface in the day and night cycling of temperatures

Answer 2

The given conditions tell you that you have carbon, nitrogen, a few small organic compounds, heat and UV radiation. I state that for emphasis: it's the important info in the problem.

B is out. It involves sulfur and you don't have any of that in your experiment.
C is out. The experimental conditions do not include a source of electricity.
D is out. The conditions say nothing about temperature oscillation.

So we suspect it's A. And A makes sense: amino acids are made out of carbon, nitrogen and a few side chains which resemble simple organic molecules and you're told you have these molecules in solution on a heated substrate. Not a hard question, really. :D