This question is based on the following paragraph. The sentences are numbered to help you answer the question. (1) Scientists generally agree that Earth is getting warmer due to what's called the greenhouse effect. (2) A greenhouse stays warm because sunlight and heat coming through the glass roof are mostly trapped. (3) The heat doesn't radiate back into the atmosphere because it's held in by the glass. (4) Something like that happens on Earth. (5) The atmosphere acts like a blanket that keeps the Sun's heat from leaking away into space.

What is the main conclusion you are to draw from this paragraph?

AGreenhouses help most to grow more quickly.
BThe atmosphere is what keeps the planet warm.
CThe sun's heat can easily leak away out into space.
DThe greenhouse effect is changing Earth's atmosphere.

Explanation: In the given paragraph we can see an explanation of why the Earth is getting warmer due to the greenhouse effect, it explains how the sunlight and heat stay trapped on Earth, because the atmosphere acts like a blanket that keeps the Sun's heat from leaking, just like the glass in a greenhouse. From the given information, the main conclusion of the paragraph is that the greenhouse effect is changing Earth's atmosphere.