Four Criminals Engage in a Drug Dealing Enterprise, Where All

Four criminals engage in a drug dealing enterprise, where all four are actively dealing drugs together. When they are arrested the police find a fully automatic Tech-9 weapon. The other three criminals stated they had no idea the fourth criminal had a weapon. All four were charged in Federal Court.

A) The other three criminals can be charged with the fully automatic Tech-9 weapon because:
B) of the rebuttable presumption that if the leader of the group is guilty, all are guilty.
C) of the conclusive presumption that if the leader of the group is guilty, all are guilty.
D) in conspiracy cases, the rule is guilty until proven innocent.
E) it was foreseeable and done in furtherance of the conspiracy.