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. Which sentence is the paragraph's topic sentence?

A. Sentence 1 B. Sentence 5 C. Sentence 3 D. Sentence 2

Answer 1

The phrase 'topic sentence' means the sentence that best covers the main idea being presented. In the context of the illustration here sentence 1 best encapsulates the subject and should be regarded as the "Topic Sentence". This is the sentence that reads "Scientists generally agree that Earth is getting warmer due to what's called the greenhouse effect."