All of the following statements about purification of water are true, EXCEPT:
**Purification of Water**
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### Core Concept
Water purification involves the removal of contaminants and microorganisms to produce safe drinking water. The process typically involves physical, chemical, and biological methods to achieve this goal.
### Why the Correct Answer is Right
The correct answer involves understanding the steps involved in water purification. Effective water purification involves the following key steps:
- Coagulation and flocculation to remove suspended solids
- Sedimentation to remove heavy particles
- Filtration to remove particulate matter
- Disinfection to kill bacteria, viruses, and other microorganisms
### Why Each Wrong Option is Incorrect
**Option A:** This statement is incorrect because reverse osmosis is a physical method of water purification that involves forcing water through a semipermeable membrane to remove dissolved solids and other impurities. While effective, it is not the only method used in water purification.
**Option B:** This statement is incorrect because distillation is another physical method of water purification that involves boiling water and then collecting the condensed steam to remove impurities. Like reverse osmosis, it is effective but not the only method used.
**Option C:** This statement is incorrect because activated carbon is a chemical method of water purification that involves the use of activated carbon to remove impurities and improve taste and odor. While effective, it is not the only method used in water purification.
### Clinical Pearl / High-Yield Fact
A key point to remember is that the sequence of steps in water purification is crucial to achieve optimal results. The correct order is coagulation and flocculation, sedimentation, filtration, and finally disinfection.
### Correct Answer:
Correct Answer: D.