Question

An amount of ozone in the ozonosphere began to drop in-

• A. 1987
• B. 1980
• C. 1992
• D. 2000

Answer 1

The correct option is B

1980

The correct option is B:

Explanation of correct answer:

1. Ozone is a molecule that is made up of three oxygen atoms, in the stratosphere called an ozone layer.
2. In $1980$, the amount of Ozone in the atmosphere began to drop sharply.

Explanation of incorrect option:-

Option A:

Montreal Protocol in $1987$, the United Nations Environment Programme (UNEP) succeeded in forging an agreement between nations to limit chlorofluorocarbons $\left(\mathrm{CFCs}\right)$ production to half the level of $1986$.

Option C:

Project Elephants starts in $1992$ for the conservation and protection of elephants.

Option D:

Helsinki Declaration in $1989$, the majority of the nations pledged to phase out chlorofluorocarbons by the year $2000$. Production of $\mathrm{CFCs}$ has been stopped since then and$\mathrm{CFCs}$ have been replaced with hydrochlorofluorocarbons ($\mathrm{HCFCs}$).

Final answer: Hence, An amount of ozone in the ozonosphere began to drop in $1980$.