Which is a unique feature of earth?

a. the thick atmosphere—made mostly of carbon dioxide—absorbs solar radiation, heating up and make the atmosphere very hot

b. it is the smallest planet and has the shortest period of revolution around the sun.

c. the planet’s surface is covered with red, iron-oxide dust.

d. it is the only planet with permanent liquid water on its surface.

The answer is d because our oceans are our unique features because we have permanent liquid water.

D. It is the only planet with permanent liquid water on its surface.

Answer (datum point);

Your answer is d. silli hope this ! : ) i left an explanation down below if you need it: a sill forms when hot magma squeezes between layers of rock to form a hardened sheet of rock. a sill is basically a tabular sheet intrusion between old layers of sedimentary rock, volcanic beds, or in the direction of foliation inherent in metamorphic rock. the word sill means a concordant intrusive sheet.