Which underlined sound is pronounced differently in each group?

Question 1: Which underlined sound is pronounced differently in each group?

1. A. who

B. what

C. why

D. where

2. A. this

B. there

C. than

D. thank

3. A. worked

B. needed

C. wanted

D. rented

4. A. cold

B. long

C. snow

D. hold