The 'global warming' leads to

The chemical substance used to destroy the weeds in crops is called

A. herbicides

B. monoxides

C. carob-oxides

D. pesticides

Besides the forest fires as natural source of pollution, the other major sources of pollution are

A. zonal settlement patterns

B. human activities

C. falling of meteoroids

D. nucleated settlement patterns

The natural source of pollution is

A. rain forest

B. mining for minerals

C. forest fire

D. falling of meteoroids

The harmful substance released by power plants and cars is

A. carbon dioxide

B. oxygen

C. potassium

D. magnesium

The kind of land pollution in which salt content rises and land becomes unsuitable for farming is called

A. carbonization of soil

B. deoxygenating of soil

C. salinization of soil

D. oxygenation of soil