What does the 50 percent split refer to in an A/B test?

• A. It refers to half of the users seeing the original ad and half seeing the new variation
• B. The test allocates all traffic to the original
• C. The 50 percent split refers to half of users seeing the original ad and half seeing the new variation
• D. The split is based on bid adjustments

Answer: (C)

In an A/B test, the 50 percent split means traffic is divided so half of users are shown the original version and half are shown the new variation, with assignments randomized. This creates two comparable groups so you can attribute any differences in outcomes—like clicks or conversions—directly to the change being tested rather than to who happened to see it. It’s not about bid adjustments or directing all traffic to the original; those wouldn’t yield a valid comparison. A 50/50 split is common because it provides balanced data and clear signals about whether the variation improves results.