In some people, substances such as peanuts, eggs, and milk cause an immune response. This response to usually harmless substances is most similar to the 1 action of the heart as the intensity of exercise increases
2 mechanism that regulates the activity of guard cells
3 action of white blood cells when certain bacteria enter the body
4 mechanism that maintains the proper level of antibiotics in the blood
Please answer + add an explanation!!

Number 3

Explanation:

Number 3 or C is correct, "action of white blood cells when certain bacteria enter the body." This is the correct answer because white blood cells are in your body to fight off infections. some peoples immune system see these bacteria on the peanut, egg, or milk as an enemy so it tries to fight against it even though it is harmless to the body.

i think that is new experiments yield untrustworthy data and should be carefully considered, because you don't know what will happen with the experiments.

on island x the species needed to adapt because they were being subject to predators which didn't inhabit island y.