The object that attracts a negatively charged balloon must be positive. This is because opposite charges attract each other according to the principles of electric charge. So, when a negatively charged balloon is brought close to a positively charged object, the balloon will be attracted to the object. This attraction occurs because the negative charge on the balloon and the positive charge on the object create an electric force that pulls them towards each other.
Therefore, the correct answer to the question is:
- Positive
