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 available_policies ( policy_id number, policy_type_code text, customer_phone text )
TABLE: CREATE TABLE first_notification_of_loss ( fnol_id number, customer_id number, policy_id number, service_id number )
TABLE: CREATE TABLE services ( service_id number, service_name text )
TABLE: CREATE TABLE claims ( claim_id number, fnol_id number, effective_date time )
TABLE: CREATE TABLE customers ( customer_id number, customer_name text )
TABLE: CREATE TABLE customers_policies ( customer_id number, policy_id number, date_opened time, date_closed time )
TABLE: CREATE TABLE settlements ( settlement_id number, claim_id number, effective_date time, settlement_amount number )

### Question ###
Which policy type appears most frequently in the available policies?

### Accurate SQL ###

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