Once Witnesses Have Been Identified,they Should Be Separated from One

Multiple Choice

Once witnesses have been identified,they should be separated from one another and,as much as possible,isolated from other people who may be nearby.Why?

A) To prevent witnesses from seeing or hearing irrelevant matters that may taint their actual knowledge.
B) To prevent witnesses from leaving the area before they have been released by the police investigator.
C) To prevent "outsiders" from hearing what witnesses tell the police.
D) All are reasons for isolating witnesses.