Final answer:
Inoculation (option b) refers to the deliberate introduction of microorganisms into a culture medium for growth and study; it differs from incubation, which is the process of maintaining the growth conditions post-inoculation, and sterilization, which completely removes or kills microbial life.
Step-by-step explanation:
The term that refers to the purposeful addition of microorganisms into a laboratory nutrient medium is b) Inoculation. Inoculation is the process by which microorganisms are intentionally introduced into a culture medium where they can grow and reproduce.
Once the microorganisms are inoculated, they enter a lag phase where they adapt to the new environment before starting to multiply. It is distinct from incubation, which is the maintenance of appropriate conditions for growth after inoculation, and sterilization, which involves the killing or removal of all forms of microbial life from an object or environment.
Sterilization is necessary to obtain a pure culture and to avoid contamination in microbiological work. Microbes are also removed physically by filtration, or controlled through the use of substances called sterilants that can kill vegetative cells, endospores, and viruses.