To handle the import of promotion and coupon data from an SFTP location, the best approach is to create a job consisting of three steps as described in option C. The first step involves a custom script to download the files from the SFTP server—this is necessary because file retrieval from external servers typically requires specific connectivity and security configurations that are best handled in a custom-coded step. The subsequent two steps would utilize standard Salesforce B2C Commerce job steps to import the downloaded promotion and coupon data into the platform. This method ensures that the data flow is streamlined, from retrieval through to integration into the Commerce platform.