In microbiology lab, you make three different culture plates: one general purpose plate, one selective media plate, and one differential media plate. Unfortunately, you forget to label the different plates, so you do not know which is which. To determine the identity of each plate, you inoculate it with two different strains of laboratory bacteria. Which of the following results would indicate the plate you used was the general purpose media?
(A) Both organisms would grow equally well.
(B) Both organisms would grow, but they would be dyed different colors.
(C) Only one organism would grow.
(D) Only one organism would grow, and it would grow a different color.

General purpose media is a culture medium that allows the growth of any kind of organism. Generally this type of culture medium is used to analyze the biochemical properties of microorganisms, facilitating their identification.

Selective media plate, on the other hand, is used to select the species to be isolated and to prevent the growth of microorganisms that are not needed. For this reason, in this type of culture medium only one species of microorganism would grow well.

Finally, a differential media plate promotes a change in the color of bacterial colonies, making it possible to distinguish various genera and species of microorganisms, so that the two microorganisms would not grow equal.

As the general purpose media allows the growth of any kind of organism equally, it would be easy to identify which petri dish would be with this culture medium. Plaque with the general purpose media would allow both organisms to grow equally well.