A. A specific organism can always be found in association with a given disease
B. The organism can be isolated and grown in pure culture in the laboratories
C. The pure culture cannot produce the disease when inoculated into susceptible animal however the causative organism isolated from pure culture can do so.
D. It is possible to recover the organism in pure culture from the experimentally infected animals

A. 3
B. 5
C. 4
D. 6