When a negatively charged balloon is brought near a neutral wall, the charges in the wall will rearrange due to electrostatic induction.
A negatively charged object, such as the balloon, will repel the negative charges (electrons) in the wall, causing them to move away from the side of the wall nearest the balloon. This results in the side of the wall closest to the balloon becoming positively charged (due to a deficiency of electrons), while the side farther from the balloon retains a negative charge.
Therefore, the correct answer is:
The wall will have its positive charges on the side closer to the balloon.