Alternative component in BOM

Hi all ,

Basically i need solution for the below scenario..........

1.FG -1 -

> COMP1 ( one of component for finish product FG-1 ) --- A-M1 (OR) A-M2 (OR) AM3 .

FG -2 -

> COMP12 ( one of component for finish product FG-1 ) --- A-M1 (OR) AM3 .

In the above case, there is a option to use alternative components for the COM1 or COM2 for the production of FG1 or FG2

respectively.

In which method i can use effectly to use the alternative components for production through BOM.

I checked the Alternative item in BOM , wile run mrp , system create the Dep remt for the all the alternatives, insteaded of one of the component. i donot want to use the Usge probability , since i need to use any of the component dep upon the stock.