Someone who formulates ingredients for a new drug is working in which field?

The correct choice is pharmaceutical manufacturing because this field specifically focuses on the development and production of medications, including the formulation of ingredients for new drugs. Professionals in pharmaceutical manufacturing work on creating new drug formulations, which involves determining the appropriate ingredients, dosages, and delivery methods to ensure efficacy and safety. This process is critical for bringing new medications to market and often includes rigorous testing and compliance with regulatory standards.

The other fields listed do not directly relate to the formulation of ingredients for drugs in the same way. Medical forensics pertains to the application of science in legal contexts, often involving the analysis of biological evidence. Animal and plant biotechnology generally focuses on the genetic modification and improvement of organisms but does not primarily address the development of pharmaceuticals. Microbiology, while important for understanding pathogens and the biological mechanisms of drug action, is more concerned with studying microorganisms rather than the formulation of drug ingredients.