____ from space, our earth, with water covering 70% of its surfa

____ from space, our earth, with water covering 70% of its surface, appears a “blue planet”.
A、Seen
B、Seeing
C、To be seen
D、Having seen
【正确答案】：A
【题目解析】：seen 在这里做非谓语，相当于 if it's seen