In which phase should you first run the SAP Readiness Check for SAP S/4HANA in a "Selective Data Transition" transition path, in a System Consolidation scenario that includes conversion from SAP ERP? Please choose the correct answer.

In which phase should you first run the SAP Readiness Check for SAP S/4HANA in a "Selective Data Transition" transition path, in a System Consolidation scenario that includes conversion from SAP ERP? Please choose the correct answer.
A . Realize
B . Prepare
C . Explore
D . Discover

Answer: D