Leading questions can be used to prejudice results. Consider alternate ways to ask sensitive questions Some questions are obviously sensitive. Income, drug or alcohol consumption and sexual habits are clear examples of topics that must be asked about carefully. Respondents might be unwilling to admit that they did not vote, because of civic pride or embarrassment. Sometimes they have an emergency, or are ill, or simply can't get to the polls.
Useful answers are just as important as good questions.
This is the most important rule to follow when providing response options. If response options are not mutually exclusive, the respondent will have more than one legitimate place for their answer. You must also ensure that the response options you provide cover every possibility. But, they would not work if you wanted to know about broader consumption habits. If the list of choices is too long, an open ended-question might be a better option.