Which of the following combinations is incompatible in a same IV line?

The correct answer involves understanding the compatibility of different medications when administered through the same IV line. In this case, ondansetron and lorazepam are both significant because ondansetron is an antiemetic, commonly used to prevent nausea and vomiting, while lorazepam is a benzodiazepine utilized for anxiety and sedation.

When these two are mixed in the same IV line, there's a risk of precipitation or other chemical interactions that can lead to reduced effectiveness of one or both drugs, or even potentially harmful effects. Therefore, they should be administered separately to avoid any incompatibility issues.

The other combinations listed may have their own specific considerations, but they are generally known to be either compatible or do not exhibit the same level of incompatibility as ondansetron and lorazepam when administered together. Thus, recognizing the incompatibilities in IV medication administration is crucial for safe patient care.