Answer
Scenes A and B demonstrate the law of multiple proportions, while scene C does not. The molecule with two red spheres is oxygen gas. The molecule with two green spheres is chlorine gas. The molecule with one green sphere and two red spheres is chlorine oxide ($ClO_{2}$).
Work Step by Step
The law of multiple proportions states that whenever molecules join together, they always do so in perfect ratios. Scene A perfectly demonstrates this as you see both the oxygen and chlorine gas molecules separately and then when they combine you see 1 chlorine atoms for every 2 oxygen atoms. Scene B also demonstrates the law of multiple proportions and scene C does not since the atoms are not joining together.
