Help with Address Book script

Hello all
I am trying to write a simple script to get last names from specific records in Address Book. If I write the id into the script:

tell application “Address Book”
last name of (person id “4579EE5F-1287-11DA-A7AB-003065C1FA46:ABPerson”)
end tell

it returns the last name

If I try to set a variable to the current found card:

tell application “Address Book”
set thisPerson to selection
last name of thisPerson
end tell

it returns the error:

“Can’t get last name of {person id "4579EE5F-1287-11DA-A7AB-003065C1FA46:ABPerson" of application "Address Book"}.”

Is this a syntax problem or am I way off base?
Thanks for your help

this seems to work;

tell application "Address Book"
	set thisPerson to selection
	
	set LastName to (last name of the beginning of thisPerson)
	
end tell

The Class of thisPerson is a list with one item in it, so

'the beginning of thisPerson

is the first item and has a class of Person

This version might make help as well;

tell application "Address Book"
	set currentSelectionList to selection
	set CurrentPerson to the beginning of currentSelectionList
	set LastName to (last name of CurrentPerson)
end tell

I assume this is because the selection can be more than one person.