An engineer set up an A/B test in an Amazon CloudWatch Evidently project with two feature variations: Variation A and Variation B. The engineer now wants to test only Variation A and have Variation A always returned when the application's endpoint is called. What is the correct way to force Variation A for only the engineer's use?

CloudWatch Evidently feature overrides allow specific users or segments to consistently receive a designated variation, bypassing the standard A/B test allocation. By adding an override targeting the engineer's user identifier and setting it to Variation A, the engineer will always experience Variation A without affecting the ongoing A/B test for other users. The other options are incorrect because: setting a feature override with an identifier set to Variation A and 100% variation percentage would force Variation A for all users, not just the engineer; adding an experiment to the project with the identifier set to Variation B and 0% traffic allocation would prevent Variation B from being served to anyone, but wouldn't force Variation A for the engineer; and adding an experiment using the AWS account ID as the identifier is not how Evidently targets individual users for overrides.