Is it ensure, insure, or assure?
((species Cervus nippon), gregarious, forest-dwelling deer, family Cervidae (order Artiodactyla), native to eastern Asia. The sika was long considered sacred in Japan and is valued in China for its antlers, which are used in traditional medicine. A small to medium-sized deer, it has a white rump and a white-spotted coat. The male has four-tined antlers.