___fruit do you like?-I like strawberries.A what B which 请问为什么不能选which

which后面要有选项的,比如你在大街上遇到一陌生人：which fruit do you like?人家怎么知道你所知的是哪几种水果?你应该这么问which fruit do you like?strawberries or apples?或者就直接问what fruit do you like?...那如果在特定的情况下 比如说有一大桌子的水果就指着这张桌子让后问whichfruit do you like ?这样可以吗？