Matrix Products: Consider the matrices $$A = \begin{pmatrix}3&6&2\\8&10&6\end{pmatrix}, B = \begin{pmatrix}3&8&5&6\\5&8&8&6\\ 3&6&3&6\end{pmatrix},\textrm{ and } C = \begin{pmatrix}9&9\\9&4\\8&8\\6&7\end{pmatrix}$$
Of the possible matrix products $ABC, ACB, BAC, BCA, CAB, CBA$,
which make sense?

A. ( ACB, BAC, CAB ) only
B. ( ACB, BAC, CBA ) only
C. ( ABC, BCA, CAB ) only
D. all of them
E. none of them