What is the name of the natural drug derived from coca plant leaves?

Cocaine is the natural drug derived from the leaves of the coca plant. It is classified as a powerful stimulant that affects the central nervous system. The process to extract cocaine from coca leaves involves a series of chemical steps that concentrate the active compounds found within the leaves, leading to the production of the substance commonly associated with both medicinal and harmful effects. Cocaine has a long history of use, both as a traditional stimulant and more recently in various forms of illegal trade.

The other substances listed, while also notable, are derived from different plants and sources. Heroin is synthesized from morphine, which is derived from opium poppies. Marijuana comes from the cannabis plant and contains tetrahydrocannabinol (THC) as its primary psychoactive compound. Opium is itself derived directly from the opium poppy and contains several different alkaloids, including morphine and codeine. Each of these drugs has different origins and effects, further highlighting why cocaine is the correct answer to the question posed.