B - plural nouns
these and those are in the plural tense and should be used plurally
<span>1) Decide what you want to learn from administering your questionnaire.
2) Plan questions that will help you get the information you need.
3) Use closed-ended questions to gather specific answers.
4) Use open-ended questions to solicit feedback.
5) Ask questions in such a way as to avoid confusion and bias.</span>
