51: Radioactive element which has been found to have large reserves in India is:

(a) Thorium

(b) Uranium

(c) Radium

(d) Plutonium
52: With reference to the mineral resources of India, consider the following pairs:

Mineral : 90% Natural sources in

1. Copper : Jharkhand

2. Nickel : Orissa

3. Tungsten : Kerala

Which of the pairs give above is/are correctly matched?

(a) 1 and 2 only
(b) 2 only
(c) 1 and 3 only
(d) 1, 2 and 3
Explanation:
Bihar and Jharkhand (44%) and Rajasthan (20%)
Nickel : Most of nickel reserves of India (92%) are found in Cuttack, Keonjhar and Mayurbhanj districts of Orissa.
Tungsten : Produced in Degana mine in Rajasthan.
53: Biodiversity forms the basis for human existence in the following ways:

1. Soil formation
2. Prevention of soil erosion
3. Recycling of waste
4. Pollination of crops

Select the correct answer using the codes given below:

(a) 1, 2 and 3 only
(b) 2, 3 and 4 only
(c) 1 and 4 only
(d) 1, 2, 3 and 4
54: An objective of the National Food Security Mission is to increase the production of certain crops through area expansion and productivity enhancement in a sustainable manner in the identified districts of the country. What are those crops ?

(a) Rice and Wheat only

(b) Rice, Wheat and pulses only

(c) Rice, wheat, pulses and oil seeds

(d) Rice, Wheat, pulses, oil seeds and vegetables
Explanation:
The National Development Council (NDC) in its 53rd meeting held on 29th May, 2007 adopted a resolution to launch a Food Security Mission comprising rice, wheat and pulses to increase the production of rice by 10 million tons, wheat by 8 million tons, and pulses by 2 millions tons by the end of Eleventh Plan (2012012) Accordingly, a centrally sponsored scheme, National Food Security Mission has been launched from 2007-08 to operationalize the above mentioned resolution.
55: Forest areas have been labelled as 1, 2, 3 and 4 in the rough outline map given:


Among these, those which were threatened in 1997 by a serious epidemic include

(a) teak forests of 3 and 4
(b) oaks forests of 1 and sal forests of 2
(c) sal forests of 3
(d) sandalwood forests of 4
Explanation:
The place marked '3' indicates sal trees of Madhya Pradesh. They were affected in 1997 by the insects.