How many ordered triples of positive integers (a,b,c) are there such that (2a+b)(2b+a)=2c?<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>None of the preceding