Which one of the following statements regarding 'Exit Poll' is correct?

1. A'Exit Poll' is a term used to denote a post-election survey of voters regarding the candidate in whose favour they had exercised their franchise
2. B'Exit Poll' and 'Opinion Poll' are one and the same
3. C'Exit Poll' is a device through which results of voting can be most exactly predicted
4. D'Exit Poll' is an administrative device made recently by the Chief Election Commissioner to prevent impersonation