The blue curtain is a term used to describe:
a. police reluctance to express personal feelings with each other.
b. the police practice of shrouding the windows and doors of the briefing room when confidential information is disseminated at roll call.
c. the secrecy and insulation from others in society that is a consequence of the police subculture.
d. the sheet used to drape the coffins of slain police officers.