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 table_name_40 ( opinion_research_centre__opc_ VARCHAR, party VARCHAR )

### Question ###
What is Opinion Research Centre (OPC), when Party is Conservative?

### Accurate SQL ###

SELECT opinion_research_centre__opc_ FROM table_name_40 WHERE party = "conservative"