The question requires passing a hyperparameter named 'reg_rate' to a training script using ScriptRunConfig. In Azure ML, hyperparameters are passed to scripts using the 'arguments' parameter in ScriptRunConfig, which accepts a list of command-line arguments. The correct format is to use '--reg_rate' followed by the value. Option B shows the proper syntax: arguments=['--reg_rate', 0.1], which creates a command-line argument that the script can parse. The community discussion shows 100% consensus on B with upvoted comments confirming it's correct. Other options either use incorrect parameter names (like 'hyperparameters' which is for HyperDriveConfig, not ScriptRunConfig) or wrong syntax for passing arguments.