Sheetal has taken an empty bottle and Balloon fixed a deflated balloon on its mouth. She placed the bottle in a container filled with hot water. After some time, the balloon gets inflated as shown. What could be the most appropriate reason for this?

• A.  Air when gets heated becomes heavier
• B.         Air when gets heated becomes lighter and settles down.
• C.         Air when gets heated becomes heavier and settles down.
• D.         Air when gets heated becomes lighter and rises up.