If two balloons repel each other, they must have the same type of electrical charge. Therefore, the correct answer is positive and positive or negative and negative. Since this option is not explicitly provided, we can conclude that the balloons must have either positive or negative charges, but both cannot be positive and negative as that would result in attraction, not repulsion.
Thus, from the available options, we can deduce that the best answer based on the concept of electric charges is:
positive and positive or negative and neutral (if neutral balloon is excluded).
But the exact option isn't fully given here.