The plant Erythroxylum coca (option B) is native to South America and is the source of cocaine, a powerful drug used as a stimulant and anesthetic in medicine.
Other plants mentioned are:
Papaver somniferum: Native to the Mediterranean region, it is the source of opium and its derivatives.
Cannabis sativa: Native to Central Asia, it is the source of marijuana.
Atropa belladonna: Native to Europe, it is the source of atropine, used in medicine for its anticholinergic properties.
Thus, the correct answer is (B) : Erthroxylum coca.