Abbreviation of Choice and Consequence, a feature associated with computer role playing games where the intent is to make player choices matter.
A given choice might prevent the player from experiencing a part of the game's story or world, or eventually lead to failure of a mission or quest. This is done with the intent of either increasing the simulation aspect of the game or its replayability (and, occasionally, both).
The term was allegedly coined by Obsidian Entertainment during the development of Alpha Protocol, although the feature itself was already present in older games, such as the original Fallout series or Planescape Torment (among others).
C&C #1: I chose to join FACTION A, so now FACTION B hates me and won't allow me to join them.
C&C #2: I decided not to help COMPANION1 with his personal quest, so he died in a cutscene in the final battle.