Answer:
The answer is the Immune system (a).
Explanation:
The immune system consists of agents that help your body fight against pathogens and other invading substances. It has your white blood cells, enzymes, mucus, hydrochloric acid (in your stomach), and even your saliva. All these substances help make sure your body is rid of anything that may bring harm to you!
I'd personally say B because a warmup will reduce injury, soreness, and get you ready. Then you have your exercise. Then the cooldown helps <span>bring the heartrate down to near-normal and to get the blood circulating freely back to the heart. Stopping abruptly could result in fainting or place undue stress on the heart.</span>
His muscles are getting stronger and have to break down to do so and that process hurts.
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