How many of the following are equal to xx+xx for all x>0?<spanclass=′latex−bold′>I:</span>2xx<spanclass=′latex−bold′>II:</span>x2x<spanclass=′latex−bold′>III:</span>(2x)x<spanclass=′latex−bold′>IV:</span>(2x)2x<spanclass=′latex−bold′>(A)</span>0<spanclass=′latex−bold′>(B)</span>1<spanclass=′latex−bold′>(C)</span>2<spanclass=′latex−bold′>(D)</span>3<spanclass=′latex−bold′>(E)</span>4