Why Does metal stick to a negatively charged balloon?

A negatively charged balloon attracts metal objects because of electrostatic induction. When the balloon is brought near a neutral metal object, the negative charges in the metal are repelled, causing a redistribution of charges. This results in a positive charge on the side of the metal closest to the balloon, creating an attractive force between the negatively charged balloon and the positively charged side of the metal. Thus, the metal sticks to the balloon due to this induced charge separation.