The equation \sqrt {x \plus{} 4} \minus{} \sqrt {x \minus{} 3} \plus{} 1 \equal{} 0 has:
<spanclass=′latex−bold′>(A)</span>no root<spanclass=′latex−bold′>(B)</span>one real root<spanclass=′latex−bold′>(C)</span>one real root and one imaginary root<spanclass=′latex−bold′>(D)</span>two imaginary roots<spanclass=′latex−bold′>(E)</span>two real roots