The first sentence is correct.
A. Defensive driving courses will help to encourage better driving among teens.
The correct answer is “Sedentary lifestyles are harmful and results in disease.”
<em>The sentence that most clearly combines these sentences in a cohesive thought is “Sedentary lifestyles are harmful and results in disease.”
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The sentence that is coherent and is grammatically correct is “Sedentary lifestyles are harmful and results in disease.” It is clear, better understood, and can’t be misinterpreted. It clearly says that if an individual has a sedentary life, it could be harmful and the consequence of this is that there is a probability to cause disease.
The other options of the question were, “Sedentary Lifestyles are a result of harmful disease “, “Lifestyles that result in disease are harmful and sedentary”, and “Lifestyles that are sedentary are harmful and result in disease”.