In Supplier relation:
sid → sid, sname, city, street
sname, city → sid, sname, city, street (given)
Primary attributes are: sname, city, sid
- Check 2NF.
Part of CK → non-prime attributes? No. So, 2NF.
- Check 3NF
Non-prime attribute → Non-prime attribute? No. So, 3NF.
- Check BCNF
For every X → Y, is X a Superkey? Yes. So, BCNF.
Option A.
PS: We can't directly check BCNF. Start with 2NF (Assuming 1NF is always satisfied)