Here are the answers to the questions based on the passage provided:

**Question 1:** What is trapping the sun's heat?
**Answer:** A. The atmosphere

**Question 2:** According to the paragraph 1, all of the following are results of our planet getting warmer EXCEPT
**Answer:** B. Increasing greenhouse gas

**Question 3:** The word "it" in paragraph 2 refers to
**Answer:** C. surprising fact

**Question 4:** The word “elevated” is closest in meaning to
**Answer:** C. enlarged

**Question 5:** What is the topic of the passage?
**Answer:** D. A study on global warming