Madison's group lab is given a dish that contains sand, shells and water. How should they classify the substance they have been given?
A: The solution is a homogenous mixture because it has the same uniform appearance and composition throughout
B: The solution is a heterozygous mixture because it does not have the same uniform appearance or composition.
C: The substance is a compound because it contains several elements.
D: The substance is a pure substance because it's made up of various compounds.