The earth from here is a grand oasis in the vastness of space.

Answer: Option C

Greenland : the largest island in the world; lies between the North Atlantic and the Arctic Ocean.
Landscape : all the visible features of an area of land, often considered in terms of their aesthetic appeal.
Waterhole : a depression in which water collects, especially one that is regularly drunk from by animals.
Wetland : land consisting of marshes or swamps; saturated land.
Oasis : a fertile spot in a desert, where water is found.

Synonym of Oasis is Waterhole