Which of the following sequences of purchase-to-pay process steps is valid?

Source of supply determination .Vendor selection , Determination of requirements Purchase order handling .Goods receipt

Vendor selection .Source of supply determination , Purchase order monitoring .Goods receipt .Handling of payments

Determination of requirements .Vendor selection , Purchase order handling .Goods receipt .Invoice verification

Determination of requirements .Purchase order handling . Handling of payments .Goods receipt .Invoice verification