I believe it is D. International date line, because the question holds the answer. When you say "Different days" it kind of gives the answer away.
Hope this helps :)
The answer to this is North Korea.
What are you trying to ask??
The planet may have or may not have had liquid water on it.
The zone that is periodically submerged between the land and the ocean is the littoral zone. In addition, this oceanic zone is the one that is closest to the coastline. Common animals that usually lives in the littoral zone are chitons, crabs, green algae, snails, starfishes, and isopods.