Answer
A. molecules
Explanation
When atoms or elements combine, they are called molecules. When molecules combine they form compounds.
Carbon, Nitrogen, and Oxygen all have the same number of energy levels because periods (rows) tell the amount of energy levels an element has.
The chemical formula for aluminum flouride is C). AlF3.
Global warming, the hole inside the atmosphere in Oklahoma , california .
I would say vapor pressure, but I could be wrong. Good luck ^^
