To add a marital status option:
Go to Setup and click Settings.
Click Module Settings, then General.
Click Person Marital Status.
Click Add Person Marital Status.
Enter a description and code and click Save.
To assign this to an employee:
Search for the employee and go to their profile.
Click Person, then Profile.
Click Edit in the Sensitive Info area.
Select the relevant option from the Marital Status dropdown and click Save.