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_80291 ( "NBR number" real, "Year" real, "Original operator" text, "Class" text, "Wheel arrangement" text, "Road number" real, "Location" text )

### Question ###
Which original operator is in the 25nc class?

### Accurate SQL ###

SELECT "Original operator" FROM table_80291 WHERE "Class" = '25nc'