The complex mechanism that maintains homeostasis is believed to depend on the immune system of the intestine.
Answer:
i would say suspect 4
Explanation:
A poodle and a parrot are both mammals so suspect 1 and 3 are out of the running. Suspect 2 works in a stone quarry so it probably doesn't have sand and hay near it.
Scarlet fever was discovered in 1827, I believe