What is a primary research method involving questionnaires?

The correct answer highlights the role of structured data collection instruments, specifically questionnaires, in primary research methods. Questionnaires are designed to gather quantifiable data from a target population, allowing researchers to collect responses in a systematic and organized manner. This method enables the gathering of information on various topics, such as attitudes, behaviors, and demographics, in a standardized format.

Using questionnaires as a research tool allows researchers to achieve various goals, such as identifying trends, measuring variables, and making comparisons across different groups. They can be distributed in various settings, such as online, in-person, or via mail, making them a versatile choice for primary research.

The other options focus on different data collection methods that do not utilize structured questionnaires. For instance, gathering qualitative data solely would imply in-depth interviews or focus groups that explore themes rather than structured questions. Collecting opinions through informal conversations lacks the rigor and systematic approach inherent in questionnaires. Conducting experiments in controlled environments refers to a different research methodology that focuses on manipulating variables to observe outcomes, rather than collecting data via questionnaires.