Which diagram best represents a mixture?

Information
Five diagrams.Short description, Five diagrams.,Long description,
Five diagrams labeled A through E. Each contains 4 groupings of atoms. The atoms are either from element #1, element #2, or a combination of the two.

Diagram A has four clusters of 3 atoms each. All of the atoms are element #1.
Diagram B has four clusters of 3 atoms each. Each cluster contains 1 atom of element #1 and 2 atoms of element #2.
Diagram C has four groups of 2 atoms each. All of the atoms are element #2.
Diagram D has four groups of 2 atoms each. Two pairs are atoms of element #1, and 2 pairs are atoms of element #2.
Diagram E has four groups of 2 atoms each. Each group contains 1 atom of element #1 and 1 atom of element #2.

Answer options with 5 options
A.
A

B.
B

C.
C

D.
D

E.
E

B. B