15. Which of the following is used only in life-threatening situations when no other drug is adequate?
A.Penicillin
B.Tetracycline
C.Chloramphenicol
D.Streptomycin

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16. The susceptibility of a microorganism to antibiotics and other chemotherapeutic agents can be determined by using
A.tube dilution technique
B.paper disk plate
C.both (a) and (b)
D.none of these

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17. Most antibiotics are isolated from
A.viruses
B.aquatic microorganisms
C.soil microorganisms
D.plants

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18. Which of the following group is not the carbohydrate containing antibiotic?
A.Streptomycin & Streptothricin
B.Vancomycin & Moenomycin
C.Everninomycin & Nogirimycin
D.Erythromycin & candicidin

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19. The penicillin stable in gastric acid and suitable for oral administration is
A.methicillin
B.carbenicillin
C.closacillin
D.pencillin-G

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20. Which of the following is not an example of potent antitumer agents?
A.Anthramycin
B.Sibromycin
C.Neothramycin
D.Erythromycin

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21. More promising chemotherapeutic agents for treating viral diseases is
A.leukocytic interferon
B.fibroblast interferon
C.interferon
D.nystatin

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