Which of these numbers is the smallest? A67!(69!)−167!(69!)^{-1}67!(69!)−1B69!(67!)−169!(67!)^{-1}69!(67!)−1C6176^{\frac17}671D6−176^{-\frac17}6−71E(68.5)−2(68.5)^{-2}(68.5)−2