Question

you have been asked to write an essay about the importance of the rainforest ecosystem. which of the following contains the best thesis statement and supporting ideas for this essay?
thesis statement:
this essay will talk about the rainforest and why its important.
supporting details:

• rainforests are made of mostly trees and plants.
• it rains most of the time in the rainforest.
• many animals live in them.

thesis statement:
rainforests are one of earths most important ecosystems. i think its a good idea to protect them.
supporting details:

• rainforests have a lot of natural resources.
• there are four layers in the rainforest ecosystem.
• rainforests can have anywhere from 80 to 430 inches of rain each year.

thesis statement:
rainforests are essential to our planet, but they are being destroyed by deforestation at an alarming rate. society needs to become informed about the value of these precious ecosystems.
supporting details:

• rainforests counteract global warming by reducing the amount of solar radiation reflected into the atmosphere.
• pollution is filtered because the rainforest absorbs carbon dioxide.
• they are critical habitats for a wide range of animals and plants.

thesis statement:
i personally believe that there is no more important cause than protecting rainforest ecosystems. our planet would be a barren desert without them. we, as a society, need to rethink our everyday actions and work toward ending the destruction of these majestic halls of nature.
supporting details:

• more animals live in rainforests than you could dream of.
• some people say that the rainforests are the lungs of our planet because they are constantly \breathing in\ carbon dioxide and \exhaling\ carbon dioxide.
• over 289,000 square miles of the amazon rainforest have been destroyed since 1978.

Explanation:

A thesis statement presents the main argument or central idea of an essay. The second thesis statement ("Rainforests are essential to our planet, but they are being destroyed by deforestation at an alarming rate. Society needs to become informed about the value of these precious ecosystems") clearly states the importance of rainforests (as they are essential to the planet) and the problem (deforestation at an alarming rate), which is a strong central idea. The supporting details around it (e.g., rainforests counteract global warming by reducing solar radiation reflected, absorb carbon dioxide, are critical habitats) all support the idea of their importance and the need for awareness (implied by'society needs to become informed'). The first thesis statement is more of a personal belief and less of a focused, evidence - based argument for an essay. The third thesis statement is more of a simple fact - based statement about rainforests (e.g., having layers, rainfall amounts) without a strong argumentative stance.

Answer:

The second thesis statement ("Rainforests are essential to our planet, but they are being destroyed by deforestation at an alarming rate. Society needs to become informed about the value of these precious ecosystems") along with its supporting details (e.g., rainforests counteract global warming by reducing the amount of solar radiation reflected into the atmosphere, absorb carbon dioxide, are critical habitats for a wide range of animals and plants) is the best for the essay.