Which completion criteria will meet this requirement?

Explanations:

MaxRuntimeInSeconds defines a maximum time limit for the tuning job but does not take into account improvements in the objective metric or the convergence of the training jobs.

TargetObjectiveMetricValue specifies a target value for the objective metric, but it does not automatically stop tuning based on convergence or improvements, making it unsuitable for the requirement.

CompleteOnConvergence stops the tuning job when the algorithm detects that further training jobs are unlikely to yield a significant improvement (more than 1%) over the best training job, thus meeting the requirement for immediate stopping.

MaxNumberOfTrainingJobsNotImproving limits the number of training jobs that can run without improvement, but it does not directly address the requirement of stopping tuning based on a specific improvement threshold of 1%.