(a) Congress grass
(b) Elephant grass
(c) Lemongrass
(d) Nut grass
2. Ans: c
Explanation:
Natural barrier against mosquitoes:
- Lavender
- Marigold (or Calendula Officinalis)
- Lemongrass (Cymbopogon citratus)
- Aromatic herbs such as mint, basil, rosemary, savory, lemon balm
- Pelargonium and geranium
- as well as eucalyptus, catmint, petunia, nasturtium, etc.
About Lemongrass-
- Lemongrass commonly known as “East Indian Lemongrass” is a perennial and multicut aromatic grass. It is the source of Lemongrass oil, a good source of natural citral, which is used s a basic raw material for synthesis of a number of useful aromatic compounds and Vitamin- A. It is a main ingredient in soaps, deodorants and cosmetics. Its use as a bio-pesticide has not yet been fully tapped.
- Lemongrass oil is used in aromatherapy to reduce stress, anxiety and depression.
- Lemongrass leaves are the most commonly found plants in India. The lemongrass oil helps to get rid of mosquitoes. In addition to this, it is also used as cat, dog and even elephant repellant.
- It is widely distributed worldwide and most especially in tropical and subtropical countries. It flourishes in a wide variety of soils ranging from rich loams to poor laterite.The lemongrass cultivation has prevented soil erosion on hilly slopes.
- From being one of the largest importers of lemongrass till just a years back India became the largest exporter of it now.
Hence, option c is correct.
Read: Previous Year UPSC Environment Questions (PYQs) With Explanation 2021