To run a DataStage job in a Unix environment, the correct command should include the specification of the domain, server, and user. Among the provided options, the correct syntax that adheres to the required command structure is 'dsjob –domain is1:9445 –server is1 –user srv_etl –run dstage1 jTest101'. This command correctly uses the –user argument to specify the user and does not include any unnecessary or incorrect arguments.