The solid form of a substance is usually more dense than its liquid and gaseous forms. Similarly the liquid form is usually more dense than the gaseous form. Ice floating in water is an exception that breaks the general density rule. So option “A” is the correct option in regards to the given question. In case of ice formation, actually the density of water decreases by about 9%. This is the main reason behind ice floating in water. Pure water has the maximum density at 4 degree centigrade.