Let 𝑀 be a $$3 \times 3$$ invertible matrix with real entries and let I denote the $$3 \times 3$$ identity matrix. If $$𝑀^{−1} = adj (adj 𝑀)$$, then which of the following statements is/are ALWAYS TRUE?

A

M = I

B

bet M = 1

C

$$M^{2} = I$$

D

$$(adj 𝑀)^{2} = I$$