Which statement exemplifies destructive criticism from a supervisor?

The statement "You must be stupid if you don't know how to do that by now" exemplifies destructive criticism because it attacks the individual's intelligence and self-worth rather than addressing specific behaviors or actions that need improvement. This type of criticism is harmful and counterproductive, as it can damage the recipient's confidence and motivation.

Destructive criticism tends to focus on personal attributes rather than constructive feedback related to improvement. By making a derogatory remark about someone's intelligence, it fosters a negative environment that discourages learning and growth. In contrast, the other statements, while possibly critical, do not denigrate the individual personally in the same way and can lead to productive dialogue about performance and expectations.