The correct answer is B. In-App Feedback, as stated in the uploaded UX Designer study guide.

The scenario contains three important requirements: feedback is needed at scale, from a specific set of users, and while those users are in the flow of their work. The study guide identifies In-App Feedback as the approach that best fits that combination.

Because the feedback mechanism appears within the application context, users can respond while the newly released feature and their interaction with it are still immediately relevant. This reduces the separation between the experience being evaluated and the moment when feedback is collected.

Option A, User Interviews, can provide detailed qualitative insight, but interviews are typically more resource-intensive and do not satisfy the at-scale requirement as directly.

Option C, Survey, can collect responses from many users, but the study-guide answer emphasizes gathering feedback directly within the working context rather than through a separate feedback channel.

The Discovery principle being tested is contextual research. When the objective is to understand a recently released feature from selected users while they are actively using the product, collecting feedback inside the experience preserves useful context and supports broader participation.

Study Guide reference/topics: In-App Feedback, contextual research, feedback at scale, feature evaluation, Discovery.

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