Answer:
Based on the supporting details for Main Fact 1, the topic sentence that would you expect to read is "Excessive texting can be harmful to your physical health."
Explanation:
Main Fact 1 presents in its supporting details three points that are clear evidence of how harmful texting too much can be to people's physical health, these three fact demonstrate the damage that this activity cause on different parts of the body, then the best topic would refer to this idea and it would give a warning.
