Commander Pavel Chekov: It is Enterprise. We fired.
Captain Montgomery 'Scotty' Scott: That is not possible! All weapons visually accounted for, sir.
Captain Spock: An ancestor of mine maintained that when you eliminate the impossible, whatever remains, however improbable, must be the truth. If we did not fire those torpedoes, another ship did.
Uhura: What exactly does that mean?
Captain Spock: It means that if we cannot have fired those torpedoes someone else did.
After witnessing the trial and sentencing of Jim and Bones from the bridge of the Enterprise Spock reviews the torpedo hit on the Kronos One.