Marine animals are able to survive in water without air contact because they have adapted to obtain oxygen from water. Option 2 correctly states that marine animals take oxygen from water.

Unlike terrestrial animals that breathe air, marine animals have evolved to extract dissolved oxygen from the water through various methods. Some marine animals have specialized organs called gills that are used for respiration. Gills contain a network of blood vessels that extract oxygen from the water as it flows over them. Other marine animals, such as whales and dolphins, have lungs and must swim to the surface to take in air.

Option 1 is incorrect because marine animals do require oxygen to survive. Option 3 is incorrect because marine animals do not produce oxygen within their bodies. Option 4 is incorrect because although some marine animals may consume oxygen produced by water plants through photosynthesis, this is not their primary source of oxygen.

In conclusion, marine animals rely on extracting oxygen directly from the water through specialized organs or by surfacing for air, allowing them to survive in their watery environment.