Choose the word in which the underlined part is no pronounced the same as in the other words of the group

Choose the word in which the underlined part is no pronounced the same as in the other words of the group.
1. a.  chase               b. chop                 c. ache           d. champion
2. a.  mouth               b. sound              c. around       d. country
3. a. dentist               b. wide                 c. excited       d. tired   
4. a. clastic                b. shape              c. bladder     d. tractor