A business practitioner needs to perform an A/B test, sending test variant A to 10%...

For an A/B test focusing on both open and click-through ratios, the most comprehensive indicator to determine the winning variant is the recipient click ratio. This indicator takes into account not just the number of clicks but also how those clicks are spread across the number of recipients, giving a more accurate measure of engagement. The open ratio would only provide data on how many recipients opened the email, but not on how they interacted with it, making the click ratio a better measure of actual engagement and interest in the content of the email, which is essential for determining the most effective delivery.References:The answer is informed by general marketing practices in A/B testing and the use of performance indicators to determine the success of email campaigns.