Given effects due to ........

- Cancer of lung

- Bronchitis

- Gastric ulcer

- Emphysema

Opium, morphine, heroin, pethidine and methadone are collectively called as

Identify the molecules $(A)$ and $(B)$ shown below and select the right option giving their source and use.

Continuous use of alcohol causes

Which one of the following is thecorrect statement regarding the particular psychotropic drug specified ?

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