Answer:
Reliability.
Step-by-step explanation:
The quality Zara need to work on in order to fulfill her role more efficiently is reliability i.e being reliable to the other nurses who require the presence of a charge nurse to successfully perform or discharge their duties.
Even though Zara loves to travel and spontaneously takes up travel offers when she sees a good deal, if she's able to imbibe, develop and improve on being reliable; she would avail the other nurses her presence, attention and time by being reliable.
A reliable person refers to an individual that is accessible, unbiased, trustworthy and credible.