Answer:
Microbial control agents can be described as agents which will inhibit or prevent the growth of microbes. Hence, they will prevent the damages caused by microbes.
Microbial control agents can either inhibit the growth of microbes. In this way, the population of the microbes will not expand and hence, the effect of the microbe on a host will be controlled.
Other microbial control agents kill the microbes and hence, control the effect of microbes.