Which of the following is effectively used to remove $E. coli$ bacteria from water?

Which of the following is a hydrophilic sol?

Select the incorrect statement.

Which of the following substances is not useful in forming a lyophilic sol?

Identify the correct statements from the following:
$I$) Sulphur sol is an example of a multimolecular colloid.
$II$) Starch sol is an example of an associated colloid.
$III$) Artificial rubber is an example of a macromolecular colloid.

Which of the following is a colloid?