Answer : The correct option is, mixture
Explanation :
Mixture : It is defined as the substance that is made by the combination of two or more different components.
Pure substance : It is defined as a substance that is made by the combination of only one type of atom or only one type of molecule.
Compound : It is a pure substance which is made from atoms of different elements combined together in a fixed ratio by mass.
Element : It is a pure substance which is composed of atoms of similar elements.
According to the definition of mixture, black powder is a mixture because it is made by the combination of red particles that float to the top, black particles that sink to the bottom and a green color liquid.
Hence, the correct option is, mixture
