If x, y, and z are positive numbers satisfying x \plus{} 1/y \equal{} 4, y \plus{} 1/z \equal{} 1, \text{and} z \plus{} 1/x \equal{} 7/3, then xyz \equal{}<spanclass=′latex−bold′>(A)</span>2/3<spanclass=′latex−bold′>(B)</span>1<spanclass=′latex−bold′>(C)</span>4/3<spanclass=′latex−bold′>(D)</span>2<spanclass=′latex−bold′>(E)</span>7/3