Answer: option B through mutation
Explanation:
- Antibiotic resistance is the phenomena in which the bacteria becomes reistance to a given antibiotic and is no longer killed or harmed by it.
- Bacteria unlike humand divide rapidly and increase in large number. However, each time it divides it has to replicate its genetic material. In the process of replication there is always a chance of introducing an error which is called as a mutation.
- The mutation that occurs in a bacteria can either ber advantageous or disadvantageous. However, amongst the various type of mutations that arise in the bacteria if a particular mutation is conferring resistance to an antibiotic then in such case the bacteris gets selected by natural selection.
- The bacteria having acquired thr resistance is then able to produce more of its progenies with the same antibiotic resistance and thus, this is how the resistance gets propagated.
So, firstly the mutation is the one which gives rise to the resistance which is then spread among the bacterial population by the process of reproduction as well horizontal gene transfer.
