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 race ( CLASS VARCHAR )

### Question ###
What is the race class with most number of races.

### Accurate SQL ###

SELECT CLASS FROM race GROUP BY CLASS ORDER BY COUNT(*) DESC LIMIT 1