26. Which of the following hint(s) suggest/s that a given specimen is likely to contain anaerobic bacteria?

A. Gas in specimen
B. Foul odour
C. Presence of sulphur granules
D. All of these

27. Viable plate count can be obtained using

A. Spread plate method
B. Pour plate method
C. both (a) and (b)
D. Hemocytometer

28. In the pour plate method, the mixed culture is diluted directly in tubes of

A. liquid agar medium
B. sterile liquid usually water
C. both (a) and (b)
D. none of these

29. Treponema species from human oral cavity can be selected by using

A. pH of the medium
B. incubation temperature
C. cell size and motility
D. all of these

30. When a substance is added to a solid medium which inhibits the growth of unwanted bacteria but permits the growth of wanted bacteria, it is known as

A. differential medium
B. enriched medium
C. enrichment medium
D. selective medium