Wal-Mart has worked with Supplier X for 35 years?

Wal-Mart has worked with Supplier X for 35 years? However, after hiring a new Supply Chain Manager, Wal-Mart decides to acquire Supplier X for 2.6 billion dollars. Wal-Mart essentially implemented_________.

Vendor Managed Inventory

Forward Vertical Integration

Backward Vertical Integration

Supplier Management