Statements (1) and (2) are the most important reasons of floodbecoming a destructive natural hazard in the Ganga-Brahmaputravalley. Statement (3) is wrong as the catchment area of both therivers does not lie in the northwestern part of India. Fertile trackalong these rivers is responsible for population pressure. The upperHimalayan regions are highly unstable, hence prone to landslideand erosion.