Read the text.

Beavers in the wild build dams of sticks and dirt across streams and brooks, blocking the flow of water and forming ponds and wetlands. This behavior can cause conflicts with people when beaver dams flood roadways and property. If the dam is destroyed, the beavers will rebuild, because when they hear running water, their instinct is to dam it. Engineers cleverly resolved this issue by designing a special pipe that is inserted through the middle of a beaver dam. The pipe's end is located away from the dam and fenced off, so beavers can't block it. Water flows through the pipe, both preserving the beaver's pond habitat and protecting people's property.
Which organizational structure does this text primarily use?

This text primarily uses a cause and effect organizational structure.

wrong

I apologize for the mistake. The correct answer is problem-solution organizational structure. The text presents the problem of beaver dams flooding roadways and property and then offers a solution to this problem by describing the design of a special pipe that allows water to flow through while preventing the beavers from blocking it.