When simplified the product (1−31)(1−41)(1−51)⋯(1−n1) becomes:
<spanclass=′latex−bold′>(A)</span>n1<spanclass=′latex−bold′>(B)</span>n2<spanclass=′latex−bold′>(C)</span>n2(n−1)<spanclass=′latex−bold′>(D)</span>n(n+1)2<spanclass=′latex−bold′>(E)</span>n(n+1)3