The MERGE command allows for the creation of a new table or the complete replacement of an existing table with a new schema, which is not required in this scenario.

The MERGE command ensures that there is no duplication of data in the target table by only inserting new records from the source table.

The MERGE command combines data from the source and target tables, writes the result to the target table while removing duplicates, and maintains the existing schema, making it the most suitable option for incremental data processing under the given constraints.

The MERGE command overwrites all existing data in the target table with new data from the source table without altering the table schema, which does not meet the requirement of combining data without duplication.