Pollution refers primarily to the of air, water, and land by wastes.

A. killing
B. fouling
C. handling
D. controlling

What environmental problems do we have nowadays?

A. sand storm
B. deforestation
C. desertification
D. soil erosion
E. global warming
F. pollution

Pesticide is harmful both to people's health and the environment.

A. 对
B. 错

chemicals are natural products.

A. 对
B. 错

Pesticide is a chemical used for killing, especially.