In the given picture the Ring A at the bottom is positively charged. Another Ring B is brought and placed over it. Ring B hovers at a certain height above A. What could be the charge on Ring B.

There is a repulsion between the two rings and we know that like charges repel each other. Since Ring B is getting repelled by A as it is floating above A at a certain height so the Ring B also would have the positive charge like Ring A.