Question

Tuberculosis is a disease caused by a bacterium and can often be fatal. For several decade , antibioticre very succesful in killing tuberculosis bacteria but now strains of the bacteria have developed that can only killed by when treated for long period of time with multiple types of antibiotics. Why have the antibiotics become less effective aagainst tuberculosis

Answer 1

It was B. those bacteria that have once come in contact with antibiotics learn to avoid them and are difficult to kill.

Explanation:

I did it

Answer 2

I think it’s because the bacteria has evolved and become immune to the antibiotics.