Whan cyclohexyl bromide is treated with a base, it does undergo E2 reaction to give cyclohexene, Select correct statement(s) in this reaction

Options

A. Cyclohexyl bromide has the chair conformation with bromine atom equatorial
B. E2 reaction is not possible in this conformation as E2 reaction requires the reacting C-H and C-Br bonds to be antiperiplanar
C. There is changing of conformation to an unfavourable axial conformation

D. There is change of ring to minimise strain