| 41. | Which book written by Rachel Carson resulted in banning DDT in USA? |
| a. | |
| b. | |
| c. | |
| d. |
| 42. | Any unfavorable alteration of the environment may be called as- |
| a. | |
| b. | |
| c. | |
| d. |
| 43. | Energy resources derived from natural organic materials are called- |
| a. | |
| b. | |
| c. | biomass |
| d. |
| 44. | Total amount of living material at the various trophic levels of a food chain is depicted by pyramids of- |
| a. | numbers |
| b. | energy |
| c. | biomass |
| d. |
| 45. | Which group of vertebrates comprises the highest number of endangered species? |
| a. | Mammals |
| b. | Fishes |
| c. | Birds |
| d. | Birds |
| 46. | Two objects, A and B, have the same mass but the specific heat of A is larger than B. If both objects absorb equal amounts of energy, |
| a. | |
| b. | |
| c. | |
| d. |
| 47. | In the stratosphere, the air temperature normally: |
| a. | |
| b. | |
| c. | |
| d. |
| 48. | Disease aggravated by air pollution is- |
| a. | |
| b. | |
| c. | bronchitis |
| d. | haemophilia |
| 49. | The outermost zone of a biosphere reserve is- |
| a. | |
| b. | |
| c. | |
| d. |
| 50. | The aurora is produced by: |
| a. | |
| b. | |
| c. | |
| d. |
