Explanation:

Only statements 2&3 are correct.

• A new study has revealed that ozone pollution is significantly hindering the growth of tropical forests, leading to a loss of nearly 300 million tonnes of carbon each year.

About Tropical Forests

• Tropical forests are rich ecosystems located in tropical zones surrounding the equator. 

• They make up six percent of Earth's land surface area.

• They have a dense upper canopy of broad-leafed trees.

• These forests are known for supporting a wide variety of plant and animal life and have nutrient-poor soils with rapid decomposition.

• More than 50 percent of land-based plant and animal species on Earth can be found in tropical forests.

• They encompass both tropical deciduous forests and tropical rainforests.

• Tropical rainforests occur in regions of the tropics where temperatures are always high and where rainfall exceeds about 1,800 to 2,500 mm (about 70 to 100 inches) annually and occurs fairly evenly throughout the year. 

• Similar hot climates in which annual rainfall lies between about 800 and 1,800 mm and in which a pronounced season of low rainfall occurs typically supports tropical deciduous forests.

• The nations with the most tropical forest area are Brazil, the Democratic Republic of the Congo, Indonesia, Peru, and Columbia, in that order.

• Cameroon, the Central African Republic, Bolivia, Ecuador, Guyana, Gabon, the Republic of Congo, Malaysia, Laos, Myanmar, Papua New Guinea, India, Suriname, Venezuela, and Mexico also have vast areas of rainforest.

• Brazil is home to about a third of the planet’s remaining tropical rainforests, including two-thirds of the Amazon rainforest.

• Tropical forests play a critical part in the planet’s water cycle and are crucial carbon sinks, storing about a quarter of all terrestrial carbon on Earth.

Hence option 2&3 are correct.