In exercise 2-4, after you have obtained a pure culture plate, you use cells from a single isolated colony to
a. make a smear for a simple stain.
b. make a three-phase streak plate.
c. make a smear for a differential stain.
d. inoculate a tube of tsb.

c. make a smear for a differential stain.

Explanation:

After isolating a pure culture it is necessary to inoculate the microorganism in a differential medium. Differential culture media enable the differentiation of microorganisms or groups of microorganisms. These media contain specific dyes or chemicals for growth of desired microorganisms.

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