To provide scientific evidence regarding the sugar content in peas, particularly for detecting the presence of fructose (a type of sugar), the student should use C. Benedict's test.
Benedict's test is specifically used to detect reducing sugars, such as fructose, glucose, and other monosaccharides. While other tests like the iodine test are used for starch and the brown paper bag test checks for fats, they would not specifically help in demonstrating the fructose content in peas.
Therefore, C. Benedict's test is the most appropriate choice for her argument.