A combination of drugs is used in the treatment of tuberculosis in order to–

Correct option is A

Sol. Combination therapy is essential in TB treatment to prevent development of drug resistance by the bacteria. Using multiple drugs (like isoniazid, rifampicin, etc.) ensures that if the bacteria are resistant to one drug, others can still kill it.
Explanation of each option:
· (a) Reduce resistance of the pathogen to treatment – Correct answer. Combining drugs lowers mutation risk and ensures complete bacterial killing.
· (b) Check sensitivity of drugs – This is done via culture & drug sensitivity testing (DST), not during regular treatment.
· (c) Check reactivity of drugs – This refers to pharmacological testing, not the reason for combination therapy.
· (d) Check hypersensitivity of drugs – This is relevant for allergies, but not the primary reason for multi-drug use in TB.