Consider the following relational schema:
$\text{Suppliers}(\underline{\text{sid:integer}},\text{ sname:string, city:string, street:string})$
$\text{Parts}(\underline{\text{pid:integer}}, \text{ pname:string, color:string})$
$\text{Catalog}(\underline {\text{sid:integer, pid:integer}}, \text{cost:real})$
Assume that, in the suppliers relation above, each supplier and each street within a city has 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 $\text{TRUE}$ about the above schema?
- The schema is in $\text{BCNF}$
- The schema is in $\text{3NF}$ but not in $\text{BCNF}$
- The schema is in $\text{2NF}$ but not in $\text{3NF}$
- The schema is not in $\text{2NF}$