Answer:
redirection of rivers away from it in order to irrigate crops
Step-by-step explanation:
The Aral Sea was once the fourth largest lake in the world, even though it has now become smaller and smaller due to the overusage of its water. The water has been diverted for irrigation to solve the problems of a recent drought which has caused it to shrink.
Therefore, the shrinking of the Aral Sea is a direct result of redirection of rivers away from it in order to irrigate crops.