Which two recommended steps can be done to prevent this looping issue?

Universal Containers (UC) sends Order data to an external ERP system via ESB. UC sends an outbound message on update or Order to ESB. Once ESB completes creating the Order in the back-end ERP, it send back the Order with the Order Number from the ERP. During development, UC is experiencing an issue. When the Order is updated by ESB, it again fires a workflow rule that sends the outbound message again.

Which two recommended steps can be done to prevent this looping issue?
A . Write an Apex trigger to send an outbound message to ES
C . Update workflow rule conditions to exclude the ERP Order Number field update.
D . Update workflow rule conditions to exclude the Integration User.
E . Update the outbound message to exclude the Integration User.
F . Update workflow rule conditions to exclude the ERP Order Number field update.

Answer: C