Final answer:
The default data transforms pyDefault and pySetFieldDefaults are created during Case Creation within Pega Platform to initialize and set default values for case properties.
Step-by-step explanation:
The default data transforms pyDefault and pySetFieldDefaults are created b) During Case Creation. These data transforms are automatically created in Pega Platform when a new Case Type is generated. The pyDefault data transform is used to initialize case properties when a case is created, while pySetFieldDefaults can be used to set default values for fields before a case is presented to a user for the first time.