When Air Masses Meet: Author's Purpose

Why did the author most likely write this passage?

• A.To teach readers about weather systems
• B.To advertise a product for sale
• C.To entertain readers with a ghost story

Authors use examples to explain their ideas. Which sentence from the passage gives an example?

• A.They are created by the movement of air masses, which are large bodies of air with…
• B.When these air masses meet, they can create different weather conditions.
• C.For example, when a warm, moist air mass meets a cold, dry air mass, it can…