Which of the Following Is a True Statement $A C = 1$

Multiple Choice

Which of the following is a true statement

A) If A and C are matrices and $A C = 1$ , then $C A = I$ .
B) Given $M = \left[ \begin{array} { l l } h & c \\g & b\end{array} \right]$ , if $h b - c g = 0$ , then M has an inverse.
C) If A, X, and C are matrices, and $A X = C$ , then $X = C A ^ { - 1 }$ .
D) If A and C are matrices and $A C = 1$ , then $C A = I$ and if A, X, and C are matrices, and $A X = C$ , then $X = C A ^ { - 1 }$ is true.
E) None of these statements is true.