You have a System Center 2012 R2 infrastructure that has Orchestrator and Service Manager
installed.
Integration between Orchestrator and Service Manager is configured.
You need to ensure that when a change request is made in Service Manager, the following
requirements are met:
The ticket number is logged to a file.
The file contains the ticket numbers for every change request.
Each time a ticket number is logged to the file, an email message is sent to an administrator.
Which activities should you use in a runbook?

A.
Monitor Object, Insert Line, and Send Email

B.
Get Activity, Append Line, and Send Email

C.
Monitor State, Insert Line, and Send Email

D.
Monitor Object, Append Line, and Send Email

Explanation:
http://technet.microsoft.com/en-us/library/hh549275.aspx
You do not know when the action should take place. So you need the monitor to trigger your action
(not the other way around). The get activity is used when a runbook is already running.
http://technet.microsoft.com/en-us/library/hh206072.aspx
Above states to use the Append Line command for logging purposes (which is not described as such
for the Insert Line command).
“Use the Append Line activity to append lines to a log file to create audits trails of runbooks.”