The most difficult thing about exploring the ocean is its size. The ocean is almost two-and-a-half times as big as all the land on Earth. In addition, the ocean is very deep—up to seven miles deep in parts! What is true about the relationship between the ocean and the land on Earth? A There are only seven square miles of ocean in the entire world. B The amount of ocean equals the amount of land. C There is more than twice the amount of ocean as land. D The total amount of land is seven times that of the ocean.