Restricting balancing segment value by legal entity

 Hi,

1)I have following values in my segment value set

01,02,03,04,05,06

2)Created a new ledger and attached two legal entity

Legal Entity 1 with BSV 01 and 02

Legal Entity 2 with BSV 03 and 04

3)Created one operating  unit for each legal entiry OU1 and OU2

4)Created new Accounts payable responsibiilty with new ledger and operating unit OU1

My questions

a)Can I restrict the the balancing segment value for Accounts payable responsibility with 01 and 02 only.Because I am using Operation unit OU1 which is under Legal entity 1 which BSV 01 and 02

b)If NO

Whats the pupose of assigning BSV to a legal entity?

c)If YES.I have tried in 12.0.4 and 12.1.1, it shows all values,ie 01,02,03,04,05,06