What is the leading nonpoint source of water pollution? 

A)  agriculture 
B)  runoff from city streets and storm sewers 
C)  municipal landfills 
D)  industrial wastes

Nonpoint Source

Pollution that comes from many diffuse sources rather than a single, identifiable source, often affecting water quality.

Water Pollution

The contamination of water bodies (e.g., lakes, rivers, oceans, aquifers) with substances harmful to life, which can be detrimental to plants, animals, and human health.

Agriculture

The practice of cultivating the land and raising livestock to produce food, fiber, and other products.