In the case in the text,Grace Label,Inc.v.Kliff,the court held that:

A) the parties' course of dealing was irrelevant in deciding whether Kliff breached the contract because Barcel was responsible for printing the cards.
B) course of dealing between the parties was admissible to explain or supplement the contract.
C) course of dealing between two parties is irrelevant when a third party that has never been a party to a contract before is part of the agreement at issue.
D) course of dealing between the parties demonstrating that Barcel was reasonable in assuming that the same card material would be acceptable.