How system is determine that which subinventory should be picked

 Hi,

As per My business scenario We have three Sub inventories like A , B, C And material is lying in A, B , C

  Example :-   Item-  TEST

Sub inventory                     On hand  QTY

A                                           5

B                                           5

C                                           5

If we want to ship this material 1 Qty then How system determine that which sub inventory should be picked.

Pls Let me know.

Rgds

Naveen