I agree with the person above - I'd say the correct answer is B. The greenhouse effect is changing Earth's atmosphere.
A is incorrect because the excerpt says that the atmosphere keeps the Sun's heat from leaking away into space. C is incorrect because it is the greenhouse effect that keeps the planet warm. D is not even mentioned in the text, which means that only B is correct.
The activity which is a way for students to make a positive digital footprint is the A. Blog posts.
He was kidnapped by his father's servant.
