Many people take their pulse after their exercise to check their heart rate and to find out if they are exercising at a healthy pace.
Answer:
B. more difficult when your close friends smoke.
Explanation:
Especially when one is younger and/or has been with your friends in a long term, it may be "more" pressuring to do things with your long-time close friend, even if it is detrimental to your health. B, is the best answer choice for this question.
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The answer to the question is a