You're a moron, that is NOT WHY WE HAVE DRUG RESISTANT TB!
The reason we have drug resistant TB if because people that became infested with TB got cheap treatment, mostly those that were in prisons and the like. The medicines became expensive and the prisoners became difficult to work with which overall led to the people not using the drugs. With modern medicine, if you don't take the full dosage for the full duration, the strain of bacteria can grow to be resistant to that strain of medicine, leading to a new form of medicine being used. When this medication is administrated, if it is not carried out to its full extent then the drug can become resistant to that one as well. So on and so forth, now we find ourselves in an era where we fight new strains of bacterium that are highly resistant. You can thank Russia for the TB, it started in prisons in Siberia.