Final answer:
The latent unsafe condition in the system that contributes to the resident's error is fatigue.
Step-by-step explanation:
The latent unsafe condition in the system that contributes to the resident's error is fatigue. Fatigue is a result of the resident nearing the end of her 18-hour work shift, which can impair her cognitive functioning and decision-making abilities. This fatigue may have caused her to make the error of closing the "U" in the insulin dose prescription, resulting in a dose that is ten times stronger than needed.