passage is ............ . A) the distribution of animals all over the world
B) passing of micro-organisms from the tamed animals to the wild ones
C) simplicity of the curing methods of contagious illnesses
D) the expansion of the human populations to the wilderness
E) changing of the climates in the habitats of the wild animals
107- The extinction of amphibians in the rain forests of Central America and Australia could have been caused by .................. . A) some infectious diseases that are still unknown
B) the expansion of mankind to new fertile regions
C) a fungal disease which has been detected lately
D) the fact that ancient people were ignorant of health-care
E) unsanitary living conditions ancient tribes were in
