What procedures are essential for verifying the accuracy of a compounded sterile preparation?

The chosen answer is correct because it encompasses crucial procedures that are essential for verifying the accuracy and safety of a compounded sterile preparation. Double-checking calculations is vital to ensure that the exact dosages and concentrations are prepared, which directly affects patient safety and treatment efficacy. Ensuring proper labeling is equally important because accurate labels provide clear information on the preparation's contents, dosage, and usage instructions, reducing the risk of medication errors. Verifying ingredient sources is critical to confirm that the materials used are authentic, uncontaminated, and of high quality, which is essential for maintaining sterility and the overall integrity of the compounded preparation.

In contrast, the other options include procedures that, while important in the pharmacy practice, do not specifically address the verification of compounded sterile preparations as effectively. For instance, calculating costs is relevant to the pharmacy's operational aspects but does not impact the quality or accuracy of the compounding process. Proper clothing is more focused on personal protective equipment for infection control rather than directly verifying the preparation's accuracy. Thus, the chosen answer highlights the three most pertinent procedures aimed at ensuring the precision and safety of compounded sterile medications.