List the last name of the members of the club that attended the women's soccer event.
members of the club refers to position = 'Member'; 'Women's Soccer' is event name;
SELECT T3.last_name FROM attendance AS T1 INNER JOIN event AS T2 ON T2.event_id = T1.link_to_event INNER JOIN member AS T3 ON T1.link_to_member = T3.member_id WHERE T2.event_name = 'Women''s Soccer' AND T3.position = 'Member'