Can you solve these physics riddles? ft Simone Giertz - Part 1/3

The heavier one. i have two explanations for it. 
1. the heavy ball has a higher terminal velocity, so it goes faster, and resistance increases with speed. 
2. terminal velocity is reached when the force of gravity and resistance cancel each other out. The force of gravity of a ball with greater mass is greater, so the air resistance must be greater as well.