A call-back system requires that a user with an id and password call a remote server through a dial-up line, then the server disconnects and:
A. dials back to the user machine based on the user id and password using a telephone number from its database.
B. dials back to the user machine based on the user id and password using a telephone number provided by the user during this connection.
C. waits for a redial back from the user machine for reconfirmation and then verifies the user id and password using its database.
D. waits for a redial back from the user machine for reconfirmation and then verifies the user id and password using the sender's database.
A. dials back to the user machine based on the user id and password using a telephone number from its database.
B. dials back to the user machine based on the user id and password using a telephone number provided by the user during this connection.
C. waits for a redial back from the user machine for reconfirmation and then verifies the user id and password using its database.
D. waits for a redial back from the user machine for reconfirmation and then verifies the user id and password using the sender's database.