set 2 MCQ Questions & Answers Detailed Explanation

Question : 1

Biochemical Oxygen Demand, (BOD) is a measure of organic material present in water. BOD value less than 5 ppm indicates a water sample to be __________.

a) poor in dissolved oxygen

b) highly polluted

c) rich in dissolved oxygen

d) not suitable for aquatic life

Question : 2

Phosphate pollution is caused by

a) weathering of phosphate rocks only

b) agriculutral fertilizers only

c) sewage and agricultural fertilizers

d) phosphate rocks and sewage

Question : 3

People drinking water from a shallow handpump are likely to suffer from the diseases

1. cholera
2. typhoid
3. jaundice
4. flourosis

a) 1, 2 and 3

b) 1, 2 and 4

c) 2, 3 and 4

d) 1 and 3

Question : 4

Consider the following statements:

1. Use of fertilizers has role on water pollution
2. Excessive use of pesticides help to decrease water pollution.

a) 2 only

b) 1 only

c) 1 and 2

d) None

Question : 5

Frequent occurrence of water blooms in a lake indicates

a) oxygen deficiency

b) excessive nutrient availability

c) nutrient deficiency

d) absence of herbivores in the lake

Question : 6

Statement I :
Coal-based thermal power stations contribute to acid-rain.
Statement II :
Oxides of carbon are emitted when coal burns.

a) Statement I is true but Statement II is false

b) Both Statement I and Statement II are individually true but Statement II is not the correct explanation of Statement I

c) Both Statement I and Statement II are individually true and Statement II is the correct explanation of Statement I

d) Statement I is false but Statement II is true