Which one of the following is a wrong statement?
- Most of the forests have been lost in tropical areas
- Greenhouse effect is a natural phenomenon
- Ozone in upper part of atmosphere is harmful to animals
- Eutrophication is a natural phenomenon in freshwater bodies
Answer
(3) Ozone in upper part of atmosphere is harmful to animals
Solution
As per NCERT, ozone in the upper part of the atmosphere (stratosphere) forms the ozone layer, which absorbs harmful UV-B radiation of the sun and so protects animals and plants. It is ozone in the lower atmosphere (troposphere) that is harmful.
Statement (3) is wrong.
Greenhouse effect is a naturally occurring phenomenon that keeps the Earth warm, eutrophication is the natural ageing of a lake, and most forest loss has occurred in the tropics, statements (1), (2) and (4) are correct.
Answer: (3)