Read the passage about the fluoridation of drinking water According to the article, what valid claim came from the National Research Council? Since the early 1960s, fluoride has been added to many sources of drinking water to prevent cavities in OThere is no link between fluoride exposure and increased cancer risk in humans. teeth. This is called fluoridation. There are some who OThere is a possible link between fluoride exposure say that this is unnecessary and increases the risk of and increased cancer risk in humans. cancer O There is a definite link between fluoride exposure and increased cancer risk in humans and animals. in 1993, the Subcommittee on Health Effects of Ingested Fluoride of the National Research Council, part of the National Academy of Sciences, conducted an extensive study about the link between fluoridated O There is a possible link between fluoride exposure and increased cancer risk in animals drinking water and increased cancer risk. The study included data from more than 50 human disease studies and six animal studies. The Subcommittee concluded that none of the data showed a link between fluoridated drinking water and cancer. A 1999 report byy the CDC supported these findings. The CDC report