I think it might be proteins
Your lungs can begin to clean themselves
Girls develop breasts and start their periods. Boys develop a deeper voice and facial hair will start to appear. The average age for girls to begin puberty is 11, while for boys the average age is 12, there were no answer choices so I hope this helped
"gigantism" is the answer. This is because gigantism is a rare condition that causes abnormal growth in children. This change is most notable in terms of height, but girth is affected as well. It occurs when your child’s pituitary gland makes too much growth hormone, which is also known as somatotropin.
I think that answer is B sorry if I am wrong I am not 100% sure tho
