When the Congo River reaches Kinshasa, _____.

it flows into a large lake

it flows slowly into the Atlantic

its course is blocked by cataracts

it becomes an irrigation canal

Verified Answer :

If my memory serves me well, the answer should be: When the Congo River reaches Kinshasa, it flows slowly into the Atlantic. Congo River is the second largest lake in the world. It takes a long way to reach the Atlantic: In the middle it flows towards Matadi and divides into several arms and finally it freely flows into the Atlantic.

The correct answer is "its course is blocked by cataracts".  I hope this helps! :)