Which of the following correctly defines "manufacture" in the context of controlled substances?

The definition of "manufacture" in the context of controlled substances encompasses a range of processes involved in the creation and preparation of these substances. Option B accurately captures this definition as it includes both extraction, which can involve isolating substances from natural sources, and chemical processes, which may involve synthesizing substances from various chemical precursors. This comprehensive definition aligns with regulatory frameworks that consider the various methods used to produce controlled substances, whether through natural extraction methods or through chemical synthesis.

Other options do not fully encompass the definition of manufacture. The first option, focusing solely on chemical synthesis, overlooks the important role of extraction in the production of substances. The third option, which addresses research and development, pertains more to the innovation and testing of substances rather than their manufacture. The fourth option, which only relates to the sale of controlled substances, fails to address any manufacturing processes altogether. Thus, option B is the most inclusive and accurate definition of manufacture in this context.