Let D be a point on side [BC] of △ABC such that ∣AB∣=∣AC∣, ∣BD∣=6 and ∣DC∣=10. If the incircles of △ABD and △ADC touch side [AD] at E and F, respectively, what is∣EF∣? <spanclass=′latex−bold′>(A)</span>21<spanclass=′latex−bold′>(B)</span>32<spanclass=′latex−bold′>(C)</span>1<spanclass=′latex−bold′>(D)</span>89<spanclass=′latex−bold′>(E)</span>2