Which of the following statements would NOT be a proper definition for a Trojan Horse?

An authorized program that has been designed to capture keyboard keystroke while the user is unaware of such activity being performed

An unauthorized program contained within a legitimate program. This unauthorized program performs functions unknown (and probably unwanted) by the user

A legitimate program that has been altered by the placement of unauthorized code within it; this code performs functions unknown (and probably unwanted) by the user

Any program that appears to perform a desirable and necessary function but that (because of unauthorized code within it that is unknown to the user) performs functions unknown (and definitely unwanted) by the user