Which of the Following Would Be Helpful in Reducing the Chance

Which of the following would be helpful in reducing the chance of hypothesis-guessing on a measure?

A) Include more items on the questionnaires (the longer the measure, the less chance participants will guess the purpose of the study) .
B) Include fewer items on the questionnaire (the shorter the measure, the less chance participants will guess the purpose of the study) .
C) Include distractor questions to help divert attention from the true purpose of the study.
D) Increase the Cronbach's alpha coefficient for the measure.