What is an aquifer?

1. An underground well that readily gives out water on digging the land.
2. An underground pond that was once a source of water and is now buried under rocks.
3. An underground stream saturated with water that is transmitted readily on to the surface.
4. None of the above.

Assertion (A): Many states have recorded a sharp fall in the groundwater levels, ranging from 70 to 80 per cent.

Reason (R): With the increase in population the demand for water has risen.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R does not explain A.
3. A is true but R is false.
4. A is false but R is true.

Which of the following is a cause for the decline in groundwater levels?

1. Irregular and erratic rainfall
2. Urbanisation
3. Loss of vegetative cover
4. All of the above.

Sprinkler irrigation is also known as ……………. .

1. Seepage irrigation
2. Overhead irrigation
3. Protected irrigation
4. Nozzle irrigation