White blood cells that produce antibodies - Lymphocytes
Systems of blood vessels that are responsible for removal of bacteria from the blood stream - lymphatic system
Outer layer of the skin - epidermis
Inner layer of the skin - dermis
Cystic fibrosis - causes a mucus build up on the lungs, that coats the breathing tubes
The correct answer is D. Push-ups.
<em>Push-ups is the only activity which strengthens muscles and can be completed in school.</em>
Exercise helps muscles to be at rest and also makes someone feel reinvigorated. There are some exercise which are strength-building.
For example, jumping sacks, forward lunges, push-ups, arm extension and plank.
You worded your question weirdly...
There are many ways to become and stay healthy.
You need to balance your diet and follow the Food Pyramid or My Plate. You can also develop a workout plan and make it part of your everyday life. You need to make sure you get enough of you're daily required nutrients and vitamins :)
If you want a more detailed answer, make add me as a friend, I can definitely help you! I took 7 years of Cooking and Foods and nutrients