[求助]语法题

fhr6568

In geometry,an ellipse may be defined as the locus of all points,____distances from two

fixed point is constant.

A)which as the sum of

B)whose sum that the

ＡＢ怎么解释，我辨析不了．谢谢

lly72823

你给的KEY好像不正确， 您再查查， 此题偶见过， 记得不是这样的。

请指正