The correct option is D Riccia fluitans
Riccia fluitans species of Riccia is aquatic. It's common name is crystalwort. It is an aquatic floating plant of the liverwort genus. Riccia is popular among aquarists as a retreat for young fry. It is used in live-bearing tanks. It can be found floating in ponds, and often forms thick mats on and under the water surface. It normally grows quickly at the surface. When kept about two to three inches below an ordinary fluorescent bulb or in a pond exposed to full sunlight, it will form dense, bright green mats. Any single branch or antler bud can reproduce into a large colony if the plant is kept in proper conditions. It normally floats, but can also be attached to underwater objects such as logs and rocks.