Mark the letter A, B, C, or D to indicate the word that differs from the other three in the position of the primary stress in each of the following questions

Mark the letter A, B, C, or D to indicate the word that differs from the other three in the position of the primary stress in each of the following questions.

Question 3. A. prefer                    B. repair                      C. borrow                   D. allow

Question 4. A. acknowledge        B. concentrate            C. contribute              D. encourage