CITI Training Practice Exam 2024 - Free CITI Training Practice Questions and Study Guide.

When a manufacturer has an active IND for a drug being studied, it means that the drug has already been approved for use in a specific clinical trial and is currently being investigated. In order to gain a more comprehensive understanding of the drug's safety and efficacy, it is necessary to cross-reference various aspects of the drug including chemistry, manufacturing, and controls (CMC) information, pharmacology and toxicology information, and any previous human experience with the drug. Option D, "All of the above," is the correct answer as it includes all three essential aspects that must be cross-referenced. While options A, B, and C are all important components, they alone may not provide a complete understanding of the drug's potential risks and benefits. Therefore, it is necessary to consider all three aspects when cross-referencing a manufacturer's active IND for a drug being studied.