One major cause of floods is

Arapid spring snowmelt.
Blight rain over a large area.
Ca decrease in stream discharge.
Dincreased capacity of stream channels.

Verified Answer :

W0lf93

The correct answer is A. rapid spring snowmelt. When the spring times come, sometimes there's a lot of warmth that suddenly comes, especially nowadays when there's things such as global warming. So the snow melts and large amounts of water can flood the fields that are often found at the foot of a mountain or similar things.

The answer to this question is A. Rapid Spring Snowmelt. You can find the answer in Pearson Earth Science Part 1 Textbook. "A heavy downpour or rapid snowmelt can flood canyons with a mixture of soil, rock, and water." 

Hope this helps. Have a great day!