Certified Travel Associate Practice

A large natural stream of water that flows along a defined route and eventually empties into an ocean, lake, or another body of water is identified as a river. Rivers are characterized by their continuous flow and play a critical role in the water cycle, ecosystem, and even in human civilization by providing water for drinking, agriculture, and transportation.

The other options refer to different geographic or temporal concepts. Time zones relate to the longitudinal divisions of the earth for coordinating time, reefs are underwater structures formed by coral and can be found in oceans, and the Prime Meridian is a longitude line that separates the Eastern and Western Hemispheres. These terms do not pertain to the concept of a flowing body of water. Thus, recognizing the definition and significance of rivers helps clarify why they are distinguished from the other choices listed.