Correct option is A
Closed-ended questions in survey research do not allow for unusual responses that the survey researcher may not have contemplated. These questions typically offer predefined answers, which limit the respondents' ability to provide unique or unexpected responses. On the other hand, they are easier for interviewers and respondents to complete, reduce variability in recording answers, and may lead to a loss of spontaneity in respondents' answers due to the limited response options. Therefore, option (a) is not a characteristic of closed-ended questions.