Which of the following statements about surveys is true?

Surveys are an effective method for gathering data and can include various types of questions and formats, which makes the statement about the need for a representative, random sample particularly important. When surveys are designed with a representative sample, it ensures that the findings can be generalized to a larger population. A random sample minimizes selection bias, allowing for diverse perspectives and experiences to be included, which enhances the validity of the survey results.

In contrast, the assertion that surveys can only collect numerical data is incorrect because surveys can also include qualitative data through open-ended questions. The claim that surveys eliminate all biases in responses is misleading since biases can still occur based on question phrasing, the survey medium, and respondents' understanding of the questions. Lastly, stating that surveys can only be conducted in person overlooks the multitude of ways surveys can be administered, including online, over the phone, or through mail, which offers flexibility to reach a wider audience. Therefore, the requirement for a representative, random sample stands out as a key factor in the effectiveness of surveys.