A water molecule consists of one oxygen atom bonded to two hydrogen atoms by covalent bonds. Since oxygen is more electronegative as compared to hydrogen atoms, the shared electrons are attracted towards the oxygen atom. This imparts partial negative charge to the oxygen atom and partial positive charge to hydrogen atoms. The overall effect is making the water molecular a polar one. The presence of free hydrogen atoms makes water molecule to form hydrogen bonds with other water molecules and with other polar molecules. Thus, the correct answer is option B.