Freon gas causing stratospheric O₃ depletion is mainly released from

• refrigerator

• automobile

• thermal power plant

• steel industry

The true statement about 'green-house effect' is that it is caused by :

• CO₂ only

• SO₂ only

• CO₂ and SO₂

• CO₂, CFC, CH₄ and NO₂ gases

Soil carried by gravity is

• alluvial

• eolian

• colluvial

• glacial

Which of the following is not a Green-house gas?

• N₂O

• CFC

• O₃

• CO₂

Which of the following diseases is related to cadmium pollution?

• Minamata

• Pneumoconiosis

• Anaemia

• Itai- Itai

Nutrient enrichment of a lake will cause

• eutrophication

• stratification

• biomagnification

• bioaccumulation

What is bioaccumulation?

SO₂ pollution is indicated by

• Desmodium (grasses)

• Sphagnum (mosses)

• Usnea (lichens)

• Cucurbita (climbers)

Which one of the following is mainly responsible for green houses effect?

• SO₂

• CO₂

• CO

• O₂

For a clean environment, which one following is not essential?

• Producer

• Consumer

• Decomposer

• Polluter