3896: The varieties of corn can be improved by which of the following methods?
(a) Dihybrid cross
(b) Back cross
(c) Double cross
(d) Natural selection
3897: What is the role of ultraviolet (UV) radiation in the water purification systems?
1. It inactivates/kills the harmful micro-organism in water.
2. It removes all the undesirable odours from the water.
3. It quickens the sedimentation of solid particles, removes turbidity and improves the clarity of water.
Which of the statements given above is/are correct?
(a) 1 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3
3898: Lushai is the name given to tribal population living in:
(a) Nagaland
(b) Manipur
(c) Tripura
(d) Meghalaya
3899: In which one of the following places is the Shompen tribe found?
(a) Spiti Valley
(b) Nicobar Islands
(c) Nilgiri Hills
(d) Lakshadweep islands
3900: Eco mark is given to the Indian products that are
(a) pure and unadulterated
(b) rich in proteins
(c) environment friendly
(d) economically viable