This is an operational question that the interviewer uses to better understand your approach to quality assurance testing. Each organization has a different procedure for quality assurance. The interviewer wants to see if your methodology aligns with the one that they use. The best way to prepare for this type of question is to research the organization before the interview. You can find information on the job posting, their website, and talking with their quality assurance team. This will help you to better align your answers to their current practices.