Pure cultures Choose one: A. can only be obtained through serial dilution of samples. B. are isolated microbial species taken from samples that often contain multiple species. C. must be used to develop vaccines. D. can be obtained for any microbial species.

B

Explanation:

Microbial samples often contain a wide variety of microorganisms. By isolating one colony and culturing it overtime you can obtain a pure culture, in which all the cells correspond to that same culture. In some cases, some microorganisms depend on others to grow and live, so it is impossible to obtain a pure culture from them.