Let ABCD be an isosceles trapezoid such that its diagonal is 3 and its base angle is 60∘, where AD∥BC. Let P be a point on the plane of the trapezoid such that ∣PA∣=1 and ∣PD∣=3. Which of the following can be the length of [PC]?<spanclass=′latex−bold′>(A)</span>6<spanclass=′latex−bold′>(B)</span>22<spanclass=′latex−bold′>(C)</span>23<spanclass=′latex−bold′>(D)</span>33<spanclass=′latex−bold′>(E)</span>7