Write SQL query to solve given problem: Lists the last name of all clients who made a PS-type complaint and were served by TOVA.. Keep the solution inside sql tag ```sql [SQL-Query] ```
SELECT t1.last FROM client AS T1 INNER JOIN callcenterlogs AS T2 ON T1.client_id = T2.`rand client` WHERE T2.type = 'PS' AND T2.server = 'TOVA'