A data engineer wants to use Autoloader to ingest input data into a target table, and automatically evolve the schema of the table when new fields are detected. They use the below query with a blank: spark . readStream . format ( "cloudFiles" ) . option ( "cloudFiles.format" , "json" ) . option ( "cloudFiles.schemaLocation" , checkpointPath ) . load ( source_path ) . writeStream . option ( "checkpointLocation" , checkpointPath ) . ___________ . start ( "target_table" ) Which option correctly fills in the blank to meet the specified requirement ?