What would the nile river flooding be described as?

The nile river the gift of Egypt would be described as:-
Every year between June and September there would be a rainy season called Akhet- the inundation and would usually flood the river and Melting snow and heavy summer rain from the Ethiopian Mountains would come tormenting down to the river on the flat desert land. (Hope this helps).

Ibelieve that the answer is (a).