What does the receptionist say about forgetting the security alarm?

The correct answer indicates that the receptionist expressed remorse for not activating the security alarm. When someone apologizes, it conveys a sense of regret or acknowledgment of a mistake, which aligns well with the context of forgetting an important task like setting a security alarm. This would suggest that the receptionist recognizes their responsibility and is taking accountability for the oversight, which is a typical response in situations involving forgetfulness regarding security matters.

In contrast, the other options suggest different attitudes toward the situation. Regretting implies a personal feeling of sorrow but doesn’t necessarily convey the act of directly addressing the mistake to someone else, as an apology would. Complaining would suggest dissatisfaction with the situation rather than ownership of the mistake, which is not appropriate in context. Informing, on the other hand, lacks the emotional component—while it suggests communicating about the oversight, it does not imply any sense of regret or responsibility. Therefore, apologizing is the most fitting expression for the scenario described.