【单选题】Which of the following is a disadvantage of using cloud accounting software?
A.
Cloud accounting software only allows one user to access the system at any one time
B.
Financial data held in the cloud must be manually transferred between individual computers
C.
Upgrading cloud accounting software is expensive and time-consuming
D.
Users of cloud accounting software are completely reliant on the provider of the software to ensure their data is secure and to take backups of it