The full form of UNFCCC is 'United Nations Framework Convention on Climate Change'.

International Union for the Conservation of Nature and Natural Resources or IUCN - established in 1948, this is an international organization related to environmental conservation, whose headquarters is in Morges (Switzerland). This institute publishes the 'Red Data Book', in which information about endangered species of animals and plants is published.

The World Wild Life Fund or WWF - established in 1962, is an auxiliary organization of IUCN whose headquarters is in Gland (Switzerland), whose symbol is the Red Panda, which is currently an endangered species. It is called the Giant Panda named Chi-Chi.

Global warming, habitat fragmentation, and invasion of alien species are major threats to biodiversity. Encouragement to vegetarianism does not harm biodiversity; rather, it is environmentally friendly.

The 'Second Earth Summit' (Kyoto+5) was held on June 5, 1997, in Denver, where the decisions taken during the first 'Earth Summit' in 1992 were reviewed, and it was found that the desired progress had not been achieved. The correct answer is not provided in the options.

This conference was held in Copenhagen.

The atmospheric part from 15 to 55 km above sea level is called the ozone layer. Ozone gas is found in this layer. This gas actually acts as a protective shield and prevents high-energy ultraviolet rays from reaching the earth. The main chemical that depletes the ozone layer is Chlorofluorocarbon (CFC), which is used in daily life in air conditioners, fridges, plastic, foam, paint, and various types of aerosols. World Ozone Day is celebrated on September 16th.

Kiwi is a bird found in New Zealand. It is the national bird of New Zealand. It is the smallest of the flightless birds.

World Ozone Day is celebrated annually on 16th September to spread awareness about the conservation of the ozone layer.

Chlorofluorocarbons (CFCs), nitrogen oxides, and hydrocarbons are directly responsible for the depletion of the ozone layer. Carbon dioxide ($CO_2$) is primarily responsible for global warming, not ozone depletion.

The Earth Summit 2002 was organized in the city of Johannesburg, South Africa.

Acid rain is also called black rain because it occurs due to an excess of sulfur dioxide and nitrogen oxides in the atmosphere. Sulfuric acid ($H_2SO_4$), nitric acid ($HNO_3$), and carbonic acid dissolve in water and fall to earth as acid rain. Rainfall is considered acid rain when its pH value is less than 5.6.

World Environment Day has been celebrated across the world since 1972 on 5th June every year for the protection and conservation of the environment. The theme for World Environment Day 2022 is 'Only One Earth'.

World Biodiversity Day or International Day for Biological Diversity is an international festival celebrated on 22nd May. It was started by the United Nations. The theme of International Day for Biological Diversity (IDB) 2022 is 'Building a shared future for all life'.

British ecologist Norman Myers introduced the concept of Hot Spots of Biodiversity in 1988 with the aim of designating areas for in-situ conservation.

In 1952, from December 5th to 9th, the skies in London were blanketed by a thick layer of smog formed by the combination of fog and toxic smoke, leading to it being named the 'Great Smog of London'.

The major cause of landslides is the increase in the frequency of earthquakes along with human activities such as road and dam construction. Jammu-Kashmir, Himachal Pradesh, and Uttarakhand are located in the Himalayan region, where landslide events are common.

The Himalayan region is the most landslide-prone area in India due to its geological structure.

Enriching a water body with nutrients is called Eutrophication. In the process of eutrophication, plants and algae grow in the water body.

The fourth One Planet Summit was organized in a hybrid mode in Paris, France on 11 January 2021, with the aim of focusing on protecting the Earth's biodiversity. The theme of this year's summit was 'Let's act together for nature'.