Approximately what percentage of the water on earth is freshwater?

a) 0.1% b) 3% c) 50% d) 97%

Explanation:

Quadrant streak method is used to separate pure agar plate colonies.

Loop dilution is a dilution technique in which inoculum is diluted every time we sterilise the loop followed by placing on agar plate which helps to isolate pure colonies.

Selective media encourages bacterial growth. Selective media is one that has added components to it that inhibit or prevent the growth of certain forms of bacteria and encourage the growth of desirable organisms.