Question

the most likely source of water polluting pathogens is ______.
a. agricultural runoff
b. surface runoff
c. sewage discharge
d. mine drainage

please select the best answer from the choices provided

a
b
c
d

Explanation:

Pathogens (disease - causing organisms) are commonly found in sewage as sewage contains human or animal waste which is a rich source of such microorganisms. Agricultural runoff mainly carries fertilizers, pesticides, and soil particles. Surface runoff can carry various pollutants but not as many pathogens as sewage. Mine drainage mainly has heavy metals and acidic water. So sewage discharge is the most likely source of water - polluting pathogens.

Answer:

C. sewage discharge