Answer:
The correct answers are A, B and C. Oceans and rivers are barriers to human trade, movement and migration because they are a natural boundary, they divide landmasses and they can be hard to cross or navigate.
Explanation:
Our planet is characterized by the predominance of water over emerging land, that is, water covers more than 70% of the planet's surface. Therefore, many times these bodies of water form barriers that prevent in one way or another the contact between different populations, thus stopping trade, mobility and interaction.
This situation is clearly seen with respect to the oceans, which separate continents by tens of thousands of kilometers. In this way, they prevent contact between different populations, forming natural barriers to it. But it also includes smaller bodies of water, such as rivers or lakes, which also form natural borders that divide different regions or countries.
However, with technological development (specifically in terms of communications and transport) these difficulties are being remedied, allowing viable alternatives that allow these natural barriers to be overcome (for example, airplanes).
