Fill in the blank with an appropriate option.

It is important to ensure that we all have good clean water to drink that is not _________ by heavy metals or chemicals.

contaminated

The most appropriate option to fill in the blank is contaminated.

• Knotted means to tie into a knot. It does not make sense in the context of the sentence.
• Clarified means to make something clear or easy to understand. It does not make sense in the context of the sentence.
• Purged means to remove something unwanted or harmful. It is a close match to the word contaminated, but it is not the most appropriate word because it does not specifically refer to water.
• Contaminated means to make something impure or polluted. It is the most appropriate word to fill in the blank because it describes the situation where water is made impure or polluted by heavy metals or chemicals.