What is microbial antagonism?
a. the ability of the normal flora to outcompete and outgrow pathogens
b. microbes that cause food to smell bad and taste bad
c. microbes that cause disease in humans
d. the overgrowth of opportunistic organisms when the normal flora are removed by antiseptic soaps

a. the ability of the normal flora to outcompete and outgrow pathogens

Explanation:

Microbial antagonism is the mechanism microorganisms use to inhibit another organism in order to prevent its intrusion, it happens when two or more microorganisms need the same elements to survive but they are limited. An example of this is the microflora that protects the human body against pathogens through competition for nutrients, oxygen disponibility or using nocive substances against the intruders.

I hope you find this information sueful and interesting! Good luck!