Two balloons are given an electrostatic charge by rubbing them with a wool cloth. Which observation provides evidence of the force that the balloons exert on each other over a distance because of their charge?

C. Moving Balloon 1 can make Balloon 2 move without the balloons touching.

Explanation:

When two balloons are rubbed with a wool cloth, they get electrostatic charge and both become negatively charged.

If both balloons will be place close together, balloon 1 will push the balloon 2 far from itself without touching it as they both are negatively charged and things with same charges repel each other.

Hence, the correct answer is "C. Moving Balloon 1 can make Balloon 2 move without the balloons touching."