A. Lungs of the planet | Tropical rainforests are often called the “lungs of the planet” because they generally draw in carbon dioxide and breathe out oxygen. But the amount of carbon dioxide they absorb, or produce, varies hugely with year-to-year variations in the climate. So the correct option is 'amazon rainforests'. | |||||||
B. Reserpine | Reserpine is an alkaloid derived from Rauwolfia Vomitoria Root Bark. Reserpine is a naturally occurring drug that has been used for centuries in ancient India. The purified alkaloid, reserpine, was isolated in 1952 and is considered the first modern drug for the treatment of hypertension. So the correct option is 'Rauwolfia'. | |||||||
C. Anti-cancer drug | There are two chemotherapy drugs that were originally developed from yew trees: docetaxel (Taxotere) was first made from the needles of the European yew treepaclitaxel (Taxol) and was made from the bark of the Pacific yew tree. Both drugs can now be made synthetically in the laboratory. But the needles are still collected and used as part of the process of making the drugs. The collecting season tends to be from July to September So the correct option is 'yew tree'. | |||||||
D. Exotic species | Exotic species, which are also known as alien species, invasive species, non-indigenous species, and bioinvaders, are species of plants or animals that are growing in a nonnative environment. L. camara is a highly variable ornamental shrub, native of the neotropics. It has been introduced to most of the tropics and subtropics as a hedge plant and has since been reported as extremely weedy and invasive in many countries. It is generally deleterious to biodiversity and has been reported as an agricultural weed resulting in large economic losses in a number of countries. In addition to this, it increases the risk of fire, is poisonous to livestock and is a host for numerous pests and diseases. So the correct option is 'Lantana camara'. |