What is the name of the CBSA of the city with the highest average house value?
the highest average house value refers to avg_house_value;
SELECT DISTINCT T1.CBSA_name FROM CBSA AS T1 INNER JOIN zip_data AS T2 ON T1.CBSA = T2.CBSA WHERE T2.avg_house_value = ( SELECT MAX(avg_house_value) FROM zip_data ) LIMIT 1