An optical apparatus uses two thin coaxial lenses to alter the width of a laser beam. A parallel beam of monochromatic light of diameter \(D_1\) is incident normally on a converging lens with focal length magnitude \(f_1\). A diverging lens with focal length magnitude \(f_2\) (where \(f_1 > f_2\)) is placed a distance \(L\) downstream from the converging lens. In order for the light emerging from the diverging lens to form a parallel beam, which of the following gives the correct separation distance \(L\) between the lenses and the resulting beam diameter \(D_2\)?