[单选题]

For relation where primary key contains multiple attributes，no non-key attribute should be functionally dependent on a part of primary key．This relation R is at least in (66) .(66)
A．3NF
B．2NF
C．INF
D．BCNF

For relation where primary key contains multiple attributes，no non-key attribute should be functionally dependent on a part of primary key．This relation R is at least in (66) .(66) A．3NFB．2NFC．INFD．BCNF