Answer: Option C.
The balloons repelled each other without touching.
Step-by-step explanation:
The balloons repelled each other without touching is an observation that the balloons has electric charge.
Electric charge is of an object either positive or negatively charge.
The balloons are positively charged that is why they repel each other. The objects that are positively charged repel each other. That is positively charged ballin will exert a repulsive force against another positively charged balloon.