Correct answer choice is :
<h2>B) Certain proteins</h2><h2 /><h3>Explanation:</h3><h3 />
Protein is an essential ingredient of every cell in the body. Hair and nails are often made of protein. Your body uses protein to strengthen and repair muscles. You also use protein to make catalysts, hormones, and other body chemicals. Protein is an essential building mass of bones, muscles, cartilage, skin, and blood.
I think the answer would be c
Capillaries is the answer
Examples of viral infections are chicken pox and warts