Hint: For its showy, fragrant, long-lasting, and intensely colourful flowers, the genus is highly prized in horticulture. In habitat and cultivation, the plants can become quite massive and possess very large, rambling aerial root systems.
> Option A is incorrect. Rhizophora is a genus of tropical mangrove trees (collectively sometimes called true mangrove trees). Red mangrove (Rhizophora mangle) is the most notable species. Usually, it lives in intertidal zones that are inundated by the ocean every day. They exhibit several modifications to this environment, including -pneumatophores (helps to raise the plants above the water and allow them to breathe oxygen even while their lower roots are flooded), and a cytological molecular "pump" mechanism that allows them to remove excess salts from their cells.
> Option B is incorrect. Heliotropium (Trope) is a genus in the borage family of flowering plants, Boraginaceae. They are common garden plants, most notably heliotropic garden plants. Some plants are weeds, and several are hepatotoxic if ingested by excessive pyrrolizidine alkaloids in large amounts. Cases of canine death occurred due to the over-ingestion of this poisonous material, particularly to dogs and cats.
> Option C is correct. The species Vanda is a genus in the Orchidaceae family. It is mainly grown in the marketplace. These roots hang freely in the air, and a special form of tissue called velamen absorbs the moisture from the air. Sometimes epiphytic plants are called air plants since they have no roots in the soil.
> Option D is incorrect. Asparagus or sparrow grass is a perennial flowering plant species in the Asparagus family. Her young shoots are used as vegetables in the spring. The root system is adventitious, and fasciculation of the root form. They grow well in lighter soils that easily warm up in the spring and drain well; the roots are easily rotted by standing water.
Hence, The correct answer is option (C).
Note: Nearly all species in this genus are very large epiphytes found in disturbed habitat areas, and prefer very high light levels, with large root systems in the plants. This species needs regular watering and weekly feeding, and is in cultivation of very heavy feeders. They can be grown outdoors in Hawaii, and the like provided some shade is granted.