Which of the following are the effects of the release of the hormone catecholamine on a person?

Smoking damages the respiratory system by inhalation of a foreign substance, that is absorbed and residue is left behind on our lungs sponge like substance. the gas that is inhaled also increase your blood pressure and dilates your blood vessels. also the process of inhaling and exhaling the smoke it causes irritation to the throat and mouth. smoking can cause lung cancer and other respiratory and circulatory diseases. 

Answer. av valves opens;

Answeri read somewhere it was the umbilical cord; or placenta; plz check first; good luck

I'd probably say d as you would try to reassure them that everything would be ok and that they won't come to any harm.