Where must the batch identification be located to ensure GLP compliance for the test substance?

• A. The container label
• B. The protocol document
• C. The sponsor's QA file
• D. The investigator's notebook

Answer: (A)

Every GLP-compliant study hinges on clear, immediate identification of the materials being used. The batch (or lot) identification must be on the container label so that the exact substance being handled is identifiable at a glance, no matter who picks it up or when it’s used. This visible label ensures traceability from receipt through use, storage, and disposal, and it supports accurate study records and potential audits.

Internal documents like the protocol, sponsor QA file, or the investigator’s notebook are important for records and accountability, but they are not physically present on the substance itself. They don’t provide the immediate, visible identification needed for proper handling and traceability in day-to-day use.