I'm setting up an automated alert which will send an email based on changes to a Potential. I need this alert to be triggered by changes to any of 4 individual fields, but the system will only allow me to select 3 fields as triggers.

Is there any way to (A) add a fourth field or (B) does anyone have any ideas as a workaround? 

Please see the attached screenshot to see what I'm looking at.

Thanks in advance for any help.

Regards,

Chris