What is the default number of cross-validation folds with the "Tune Model Hyperparameters" module in Azure ML studio?

I presume the Azure ML studio's Tune Model Hyperparameters module is performing cross-validation, since it shows average test metrics like accuracy and precision:

However, I don't see a parameter for setting the number of CV folds nor any info in the docs about what this test set is. In the pipeline, we are only providing training data (no validation/test set):

So is the module performing CV by default? If so, what is the default number of folds? I understand how we can customize the folds by placing another module first, but I want to confirm it's actually doing CV and want to know the number of folds.