Choose A, B, C or D which has a different underlined sound

1.   Choose A, B, C or D which has a different underlined sound.

      1.   A. mouth                     B. thirsty                     C. mother                    D. fifth

      2.   A. weak                       B. wear                        C. leak                         D. beat

      3.   A. part                         B. arm                         C. art                           D. angel