36. Which of the following species/subspecies of Klebsiella produce indole?

A. K pneumoniae subspecies rhinoscleromatis
B. K pneumoniae subspecies aerogenes
C. K pneumoniae subspecies pneumoniae
D. K oxytoca

37. Primarily human pathogenic bacteria is/are,

A. Salmonella typhi
B. S paratyphi A
C. S paratyphi B
D. all of these

38. The bacteria which produce(s) β-galactosidase is/are

A. Citrobacter
B. Enterobacter
C. Serratia
D. all of these

39. Which of the following property(ies), shown by the organisms belong(s) to the family Enterobacteriaceae?

A. They are catalase-positive
B. They are oxidase-negative
C. They ferment glucose
D. All of these

40. In the Widal test, the significant titer for O agglutinins is generally

A. 1:50 or more
B. 1:100 or more
C. 1:150 or more
D. 1:2.00 or more