with the size of the whole earth, the highest mountain doesn’t seem high at all.
A. To pare
B. while paring
C. It paring
D. when pared
网友回答
A. To pare
B. while paring
C. It paring
(答案→)D. when pared
解析：考查省略句。当状语从句的主语与主句主语一致的时候，可以把主语与系动词省略，构成省略句。本题when后面省略了the highest mountain is pared.句意：当最高的山与整个地球进行比较时，最高的山也一点都不高了。