the answer is a.
Quinine comes from the bark of the cinchona tree of South America.
Quinine. (Too much quinine in one's system can lead to cinchonism.)
Quinine is made from cinchona tree
For hundreds of years, quinine from the Peruvian cinchona tree was the only drug known to be effective for treating a parasitic infection (malaria). Quinine is still used today, but synthetic derivatives, such as choloroquine, have largely replaced it.
Quinine is made from cinchona tree
Quinine is the "drug" from the bark of Cinchona tree that has got antiparasitic properties. It can be used against Malaria.
The drug called Quinine is obtained from the bark of the Cinchona tree. The drug is used to treat people suffering from malaria.
Quinidine is a pharmaceutical agent, and is a stereoisomer of quinine that originally derived from the bark of the cinchona tree.
Quinine comes from the bark of the cinchona tree.
The cinchona tree, which is native to in the Amazon rain forest. This tree's bark is the source of quinine and is the original cure for malaria.
It s a natural substance from bark. Also great for severe cramp in tablet form known as quinnine bisulphate