15. Which of the following are considered sources of "Chemical Pollutants?"
A. man made fertilizers
B. insecticides
C. pesticides
D. All the above

its probably

D. all the above

Explanation:

-

succession returns a disturbed

ecosystem to a more stable state. this is also classified into two (2) types:

primary succession and secondary succession. the primary succession arises when

a new land is transformed and a bare rock has been exposed providing an environment

that can be occupied for the first time. while, secondary succession occurs

when a previously occupied environment was disturbed that kills much of all its

community

explanation: