Aviva's company frequently needs a software specialist to update its highly unique computer systems. Aviva is trying to determine if she should pay the high salary and benefits of a full-time employee or use a contingent employee when needed. What is one reason Aviva would reject the idea of using a contingent workforce?

a. The high cost of turnover b. The high cost of training c. The high need for knowledge d. The high need for flexibility e. The high cost of labor