Good morning!
I believe the correct answer is C. Large land mass. It can't be any others because a continent is a large part of land, for example, Europe and America are continents. A large body of water would be an ocean, it's not a measure of distance, because that would be meters, kilometers, etc. It's not a measurement of time because that would be measured in days, months, years..
Hope this helps! ☺♥