The correct answer is D. 0.0001 ppm.
Phenolic compounds are a group of organic chemicals that are found in many different products, including gasoline, paint, and pesticides. They can also be formed as a result of industrial processes, such as coal burning.
Phenolic compounds can be harmful to human health, especially if they are ingested in high concentrations. They can cause a variety of health problems, including cancer, liver damage, and kidney damage.
The Environmental Protection Agency (EPA) has set a maximum contaminant level (MCL) for phenolic compounds in drinking water of 0.0001 parts per million (ppm). This means that there should be no more than 0.0001 milligrams of phenolic compounds per liter of water.
The EPA has set this MCL because phenolic compounds can cause a variety of health problems, even at low levels. The EPA recommends that people who are concerned about the health effects of phenolic compounds should install a filter on their drinking water system that can remove these compounds.
The other options are incorrect because they are higher than the EPA’s MCL for phenolic compounds in drinking water.