46. Which of the following groups of rivers have their source of origin in Tibet?

A. Brahmaputra, Ganges and Sutlej
B. Ganges, Sutlej and Yamuna
C. Brahmaputra, Indus and Sutlej
D. Chenab, Ravi and Sutlej

47. Which of the following measures are effective for soil conservation in India?

I. Avoiding crop rotation
II. Afforestation
III. Encouraging the use of chemical fertilizers
IV. Limiting shifting cultivation

A. I and II
B. II and IV
C. III and IV
D. I, II and III

48. Which of the following crops needs maximum water per hectare?

A. Barley
B. Maize
C. Sugarcane
D. Wheat

49. The watershed between India and Myanmar is formed by

A. the Naga Hills
B. the Garo Hills
C. Khasi Hills
D. the Jaintia Hills

50. The originating in the Himalayan mountain complex consists of how many distinct drainage systems of the Indian Subcontinent?

A. Two
B. Three
C. Four
D. Five