Most parents probably have little first-hand experience other than to observe the outside condition of the bus or maybe the steps leading into the bus. One wonders how many responded to the question. Unless the exterior condition of the bus is of concern, this question should be removed to make room for other, more relevant issues. Prioritizing questions is imperative to keeping a questionnaire concise and motivating respondents to complete the task. Remember the logical little things.
Cooperation is hard enough to obtain without presenting such obstacles.
Review and pre-test. Many pitfalls can be avoided with proper review and pre-testing of the questionnaire. Once a questionnaire is drafted, several sets of eyes should review it. Somewhere in the process, it can be very beneficial to have a third-party market research professional review the questionnaire as well. Such a person will have a much fresher view of the questionnaire and will be more likely to spot problems.