The answer is A. Just took the quiz and got it correct.
The cascade volcanoes were formed by the subduction of the Juan De Fuca, Explorer and the Gorda Plate (remnants of the much larger Farallon Plate) under the North American Plate alone the Cascadia subduction zone
Predicting where an earthquake epicenter will occur is easier because are patterns to look at due to the fact that they always occur near plate boundaries. Predicting when they will occur is difficult because they do not follow any certain pattern.
To reduce the risk of flooding hope I could help :)
Sand, rocks, and sediment could be carried(erosion) by wind and water
