A retiring employee receives and annual pension proportional to the square root of the number of years of his service. Had he served a years more, his pension would have been p dollars greater, whereas, had he served b years more b=a, his pension would have been q dollars greater than the original annual pension. Find his annual pension in terms of a,b,p, and q.<spanclass=′latex−bold′>(A)</span>2(a−b)p2−q2<spanclass=′latex−bold′>(B)</span>2ab(p−q)2<spanclass=′latex−bold′>(C)</span>2(ap−bq)ap2−bq2<spanclass=′latex−bold′>(D)</span>2(bp−aq)aq2−bp2<spanclass=′latex−bold′>(E)</span>(a−b)(p−q)