| Statement I: | Irrigation without proper drainage of water leads to water-logging in the soil. |
| Statement II: | Besides affecting the crops, water-logging draws salt to the surface of the soil. |
| 1. | Statement I is incorrect; Statement II is correct |
| 2. | Statement I is correct; Statement II is correct |
| 3. | Statement I is correct; Statement II is incorrect |
| 4. | Statement I is incorrect; Statement II is incorrect |
| Assertion (A): | Primary contaminants for accelerated eutrophication of lakes are nitrates and phosphates. |
| Reason (R): | Nitrates and phosphates are plant nutrients which over-stimulate the growth of algae. |
| 1. | Both (A) and (R) are True and (R) correctly explains the (A). |
| 2. | Both (A) and (R) are True but (R) does not correctly explain the (A). |
| 3. | (A) is False but (R) is True. |
| 4. | (A) is True but (R) is False. |
Consider the given two statements:
| Assertion (A): | Recycling, an essential element of e-waste management, must be carried out properly especially in developing countries. |
| Reason (R): | Informally recycling – much of it by hand in developing countries, exposes workers to hazardous and carcinogenic substances such as mercury, lead and cadmium. |
| 1. | (A) is true (R) but is False |
| 2. | Both (A) and (R) are True and (R) correctly explains (A) |
| 3. | Both (A) and (R) are True and but (R) does not correctly explain (A) |
| 4. | Both (A) and (R) are False |
| 1. | Kilobase | 2. | Dobson unit |
| 3. | Decibels | 4. | Decameter |
| 1. | The amount of some toxic substances of industrial wastewater increases in the organisms at successive trophic levels. |
| 2. | The micro-organisms involved in biodegradation of organic matter in a sewage-polluted water body consume aquatic organisms. |
| 3. | Algal blooms caused by excess of organic matter in water improve water quality and promote fisheries. |
| 4. | Water hyacinth grows abundantly in eutrophic water bodies and lead to an imbalance in the ecosystem dynamics of the water body. |
Given below are two statements:
| I: | Electrostatic precipitator is most widely used in a thermal power plant. |
| II: | Electrostatic precipitator in a thermal power plant removes ionising radiations. |
| 1. | Statement I is incorrect but Statement II is correct. |
| 2. | Both Statement I and Statement II are correct. |
| 3. | Both Statement I and Statement II are incorrect. |
| 4. | Statement I is correct but Statement II is incorrect. |
| 1. | Algal Bloom decreases fish mortality. |
| 2. | Eutrophication refers to increase in domestic sewage and waste water in lakes. |
| 3. | Biomagnification refers to increase in concentration of the toxicant at successive trophic levels. |
| 4. | Presence of large amounts of nutrients in water restricts 'Algal Bloom'. |
| 1. | Eutrophication | 2. | Humification |
| 3. | Mineralisation | 4. | Stratification |
| 1. | Amount of dissolved oxygen in the lake will decrease. |
| 2. | The lake will remain unaffected |
| 3. | Number of submerged aquatic plants in the lake will increase |
| 4. | Number of aquatic animals in the lake will increase. |