If S \equal{} i^n \plus{} i^{\minus{}n}, where i \equal{} \sqrt{\minus{}1} and n is an integer, then the total number of possible distinct values for S is:
<spanclass=′latex−bold′>(A)</span>1<spanclass=′latex−bold′>(B)</span>2<spanclass=′latex−bold′>(C)</span>3<spanclass=′latex−bold′>(D)</span>4<spanclass=′latex−bold′>(E)</span>more than 4