Answer:The respiratory and circulatory systems bring oxygen and nutrients to the cells. The respiratory and circulatory systems work together to maintain homeostasis. The respiratory system moves gases into and out of the blood. The lungs contain the bronchi, bronchioles, and alveoli.
Explanation:
Answer:
Heart.
Explanation:
A congenital heart defect (CHD) is a structural problem with the heart that's present at birth. Such defects result when a mishap occurs during heart development soon after conception – often before the mother is aware that she is pregnant.
"Pacemaker" is the one choice among the following choices given in the question that is the treatment that can also regulate heart rhythmsthat has replaced drugs in some cases. The correct option among all the options that are given in the question is the first option or option "A". I hope it helps you.