Correct option (c) Adrenaline
Explanation :
A man suddenly sees a tiger. His heart beat goes up, blood pressure etc. increases. Adrenaline is released at this time in his body from adrenal medulla. Thus, a man, after being excited starts to secrete adrenaline in large amount. It increases blood sugar. and blood lactic acid levels, along with these it increases heat production, metabolic rate and body temperature. Its coordinated actions help the body to react in stress. This is why adrenal medulla is sometimes called the gland for 'light, fright and flight'.