Hello Shailesh
Considering that you are generating planned orders using MRP, this is not possible.
MRP will always generate planned orders for the main material, in this case, product A.
The alternative here is to define a BOM for product A with B and C as co-products, another BOM for product B with A and C as co-products and a BOM for C with A and B as co-products.
In this case, when you have a requirement for B, system will use its BOM and select A and C as co-products. Dependent requirements with positve quantity (goods receipt) will be generated for A and B.
However, you should consider that that MRP does not consider the by-products and co-products receipts into the rescheduling check. The following modification notes changes the system behavior and includes these dependent reservation on the rescheduling check:
203151 - Rescheduling for dependent reservations
BR
Caetano