Scientific evidence should be used to investigate the validity of a scientific claim rather than anecdotal evidence because scientific evidence can be empirically tested and verified (option C). This means that scientific evidence is based on systematic observation, experimentation, and analysis, and can be reproduced by other scientists. Anecdotal evidence, on the other hand, represents only one or a few observations about a particular natural phenomenon (option D), and is often based on personal experiences or opinions. As a result, anecdotal evidence is not as reliable as scientific evidence, and is not a valid basis for making scientific claims.