Consider the following relational schema:Suppliers(sid:integer, sname:string, city:string, street:string)Parts(pid:integer, pname:string, color:string)Catalog(sid:integer, pid:integer, cost:real)(sid,pid are primary keys)Assume that, in the suppliers relation above, each supplier and each street within a city has a unique name, and (sname, city) forms a candidate key. No other functional dependencies are implied other than those implied by primary and candidate keys. Which one of the following is TRUE about the above schema?

• A. The schema is in BCNF
• B. The schema is in 3NF but not in BCNF
• C. The schema is in 2NF but not in 3NF
• D. The schema is not in 2NF