Final answer:
Accuracy in designing a questionnaire refers to having questions that measure what they are intended to measure, while relevancy refers to questions that are applicable and meaningful to the research objectives.
Step-by-step explanation:
In designing a questionnaire, accuracy refers to the extent to which the survey questions measure what they are intended to measure. It involves using clear and unambiguous language to avoid any misinterpretation by respondents. For example, using specific terms and avoiding vague terms can enhance the accuracy of the questionnaire. Relevancy, on the other hand, refers to the extent to which the questions are applicable and meaningful to the target population. This involves ensuring that the questions are relevant to the research objectives and that they capture the information needed to answer the research questions.