Apple Contacts- creating a group with only one of the addresses in Contact card
If members of a group in Contacts have multiple addresses or phone
  numbers, you can select which address or number to use when sending
  email to that group or when printing contact information.



Choose Edit > Edit Distribution List.
Select the group.
You can’t select Smart Groups.
Click the rightmost column header to choose the information to manage: email (address), phone (number), or (street) address.
Select an address or number for each member.


Source: From the Help menu in Contacts on Mavericks.