Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE policies (policy_type_code VARCHAR)

### Question ###
Which type of policy is most frequently used? Give me the policy type code.

### Accurate SQL ###

SELECT policy_type_code FROM policies GROUP BY policy_type_code ORDER BY COUNT(*) DESC LIMIT 1