Ephedrine or pseudoephedrine used in synthesis.

• A. One Pot method
• B. Ephedrine or pseudoephedrine used in synthesis
• C. Brake cleaner, acetone, and camp fuel
• D. Common solvents

Answer: (B)

The main idea here is identifying which substances are used as starting materials in illicit drug synthesis. Ephedrine or pseudoephedrine are well-known precursors for producing methamphetamine and related amphetamines, so they’re the choice that directly reflects a substance used in the synthesis process. This makes the option that mentions ephedrine or pseudoephedrine the best fit, because it points to the chemical used to start the synthesis rather than a method or generic solvents. The other choices describe a method or general solvents, which do not identify a specific precursor involved in the synthesis.