Deionized water is obtained by passing hard water through

Given below are two statements:
Statement-$I$: Permutit process is more efficient compared to the synthetic resin method for the softening of water.
Statement-$II$: Synthetic resin method results in the formation of soluble sodium salts.
In the light of the above statements,choose the most appropriate answer from the options given below:

Which of the following is a good scientific method to detect the presence of water in a liquid?

Describe the structure of the common form of ice.

Can you use soaps and synthetic detergents to check the hardness of water?

$D_2O$ is used in