Which statements are correct about the reaction?
A. A mixture of two amines is formed, which suggests that rerrangement is intramolecular.
B. If `R` is chiral, it migrates with retention of configuration.
C. A mixture of four different amines is formed , which suggests that a free acyl nitrene `[R-overset(O)overset(||)C-overset(..)(N: )]` intermediate is formed.
D. A mixture of two different amines and a free acyl nitrene intermediate is formed.
