Which of the statements is/are correct ?
A. (a) Diels - Alder reaction is an electrocyclic reaction.
B. (b) Both thermal stability and probability (entropy) factors are responsible for affecting the formation of cycloalkanes by intramolecular cyclisation.
C. (c)
The intermediate in the above reaction is `C^(-)CIBrI`.
D. (d)
The above step proceeds by SN mechanism (substitution by nucleophile).
