The classification is in this order: Kingdom, Phylum, Class, Order, Family, Genus Species.
The kingdom is the largest group, it contains the largest number of organisms who are the least related.
The species is the smallest group, it contains the least number of organisms who are closely related.
As you go down, from "Kingdom", species become more closely related.
So species in the same family are MORE closely related than species in the same class.
The answer would be C as it can be directly tested experimentally and observed that bacteria adapted to become drug resistant and the natural selection of drug resistant bacteria to survive and continue proliferating, thus being direct evidence of evolution
Both answers C and D are correct, however, answer D makes more sense.
Doctors would let your body's immune system fight off a bacterial infection. If the infection gets worse, then the doctors would proscribe you with some antibiotics so it'll fight off the harmful bacteria.
A symbiosis is an evolved interaction or close living relationship between organisms from different species, usually with benefits to one or both of the individuals involved.
