MongoDB exposes server parameters that can be configured through the parameter framework. Among the choices, --setParameter is the option specifically designed to set a server parameter on the mongod command line, using syntax such as mongod --setParameter < name > = < value > . A configuration file can also contain a setParameter section, but --config by itself merely tells mongod which configuration file to load; it is not the parameter-setting mechanism identified by the question. Connection-string options control how clients connect and cannot be used to configure arbitrary server runtime parameters. Option D is also incorrect because the server must already be running for mongosh to issue administrative commands. A technical nuance is important: parameters that support modification while the process is already running are changed with the administrative setParameter command, for example db.adminCommand({setParameter:1, ...}). Such runtime changes may not persist across a restart unless the value is also configured for startup. Given the options provided and the exam wording, --setParameter is the intended method, so A is correct.

Study Guide reference/topic:MongoDB Architecture and Core Operations - server parameters, --setParameter, configuration files, and runtime administration.

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