Answer: The question is incomplete.
The options are not given but the correct answer is;
They can protect the body from infection.
Explanation:
Microorganisms are microscopic organisms that are found in every environment. They include bacteria, fungi, viruses e.t.c.
The can be single celled or form colony.
Microbes are of utmost important in larger animals in that they form symbiotic relationship with them. Microbes live in or on organisms.
Microbes help in digestion of food in intestinal gut and also help prevent infections due to their activities in or on the larger animals. Their secretions help to prevent Invaders. They benefit by having shelter and nutrients they feed on from their host.