Introduction:
The process of removing insoluble impurities from water is important to make it safe for various uses. There are several methods for removing impurities from water, including filtration, sedimentation, evaporation, and decantation. However, one of these processes does not involve the removal of insoluble impurities from water.

Explanation:
The correct answer is option E, "None of these". Let's examine why this is the correct answer.

Filtration:
Filtration is a process that involves passing water through a filter to remove insoluble impurities. The filter contains small pores that trap larger particles, allowing only clean water to pass through. This method is commonly used in water treatment plants and in household water filters.

Sedimentation:
Sedimentation is the process of allowing suspended particles to settle at the bottom of a container due to gravity. When water is left undisturbed, the heavier particles sink to the bottom, leaving clearer water above. This is an effective method for removing larger insoluble impurities from water.

Evaporation:
Evaporation is the process of converting liquid water into vapor by heating it. While evaporation can help remove some impurities, it primarily targets soluble impurities rather than insoluble ones. When water evaporates, it leaves behind the solid impurities in the original container.

Decantation:
Decantation is the process of carefully pouring off the clear water from a container while leaving behind the settled impurities at the bottom. This method is commonly used to separate a liquid from insoluble solid particles.

None of these:
The option "None of these" implies that there is another method of removing insoluble impurities from water that is not listed in the given options. However, since the provided options already cover the commonly used methods for removing insoluble impurities, there is no additional process to consider.

Conclusion:
In summary, among the given options, the process of removing insoluble impurities from water that is not listed is "None of these." The other options, including filtration, sedimentation, evaporation, and decantation, are all valid methods for removing insoluble impurities from water.