Which method is used when a large number of people respond to the same set of questions?

Surveys are a method specifically designed to gather responses from a large number of people on the same set of questions. This approach allows for the collection of quantitative data that can be statistically analyzed, making it effective for understanding trends, opinions, and behaviors within a particular demographic. Surveys can be distributed in various formats, such as online questionnaires, telephone interviews, or paper forms, providing flexibility in reaching a wide audience.

In contrast, focus groups involve a small group of participants discussing topics guided by a facilitator, which limits the number of responses and is more qualitative in nature. Interviews typically involve one-on-one conversations, allowing for in-depth exploration of individual perspectives but not suitable for gathering mass responses. Observation focuses on watching user behavior in real-time without direct questioning, which doesn't involve asking the same questions to multiple individuals.