set 2 MCQ Questions & Answers Detailed Explanation

Question : 1

From which one among the following water sources, the water is likely to be contaminated with fluoride?

a) Pond water

b) River water

c) Ground water

d) Rain water

Question : 2

Which of the following statements is correct?

a) Ozone hole is a hole formed in the troposphere from which ozone oozes out.

b) Ozone hole is thinning of ozone layer of stratosphere at some places.

c) Ozone hole is a hole formed in stratosphere from which ozone oozes out.

d) Ozone hole means vanishing of ozone layer around the earth completely.

Question : 3

Which of the following is a biological method of pest control in a field?

a) Fences around the field

b) Use of pesticide

c) Use of scarecrow in a strategic position.

d) Rotation of crop.

Question : 4

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 : 5

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 : 6

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