C1 or C3 are the only two that makes sense. Never manually manipulate the hammer. My carry 1911 is C1 and stays that way in a lock box at night. The less you have to mess with loading and unloading the less chance you have of:
a) an ND due to carelessness
b) inadvertently carrying an ‘unloaded gun

C3 makes sense if you are taking about something like leaving a gun in a safe for quick but not immediate access. Don’t rely on it to deter a motivated child. IMO, there is no real place for C2 with a 1911.