What should be done prior to backing up an IOS image to a TFTP server?（）
- A Make sure that the server can be reached across the network.
- B Check the authentication for TFTP access to the server is set.
- C Assure that the network server as adequate space for the IOS image.
- D Verify file naming and path requirements.
- E Make sure that the server can store binary files.
- F Adjust the TCP window size to speed up the transfer.