Choose the word that has the underlined part pronounced differently from the others

Choose the word that has the underlined part pronounced differently from the others:

      1/         a.cucumber          b.summer                c.brush                 d.minibus

      2/         a.season               b.weather                c.week                  d.beach

      3/         a. idea                   b. kite                      c.skip                    d. twice

      4/         a. years                 b.weeks                   c. aunts                 d. maps