The third rule of validity is that:

A) a syllogism cannot have two negative premises
B) a syllogism cannot have any negative premises
C) a syllogism cannot have a negative conclusion
D) a syllogism must have a negative conclusion
E) if one premise is negative, the other must also be negative

Syllogism

A form of reasoning in which a conclusion is drawn from two given or assumed premises, each of which shares a term with the conclusion.

Negative Premises

Statements within an argument that deny or negate a particular proposition or assumption.

Validity

The quality of being logically or factually sound; in logic, it refers to an argument where the conclusion logically follows from the premises.