Explanation:

A team of scientists have identified iodic acid (HIO3) as a novel driver of new aerosol particle formation in the Arctic which is responsible for Arctic Amplification or Arctic Warming. Presence of Iodic acid in the region had not been observed previously.

• These aerosol particles influence the formation of clouds. As these clouds reflect solar radiation (known as Aerosol Radiative Forcing) but also retain heat on the Earth's surface, they have an influence on the warming of the Arctic.
• Ocean currents normally bring in warmer water from the Pacific, and colder water exits out of the Arctic into the Atlantic.
• But those currents may be changing because more melting ice is injecting the Arctic Ocean with freshwater. The missing ice also exposes the surface waters to more wind. This mixes up colder freshwater at the surface and warmer saltwater below, raising surface temperatures and further melting ice.
• Change in Albedo: When bright and reflective ice (with more albedo) melts, it gives way to a darker ocean (lowering albedo); this amplifies the warming trend because the ocean surface absorbs more heat from the Sun than the surface of snow and ice.
• A high albedo means the surface reflects the majority of the radiation that hits it and absorbs the rest.
• A low albedo means a surface reflects a small amount of the incoming radiation and absorbs the rest. For instance, fresh snow reflects up to 95% of the incoming radiation.

Hence option 4th is correct.