JPA 2.0 Locking Features

[javajeecert]

If a Persistence application locks entity x with a pessimistic lock, which statement is
true?

A. The Persistent provider will lock the database row(s) that correspond to all persistent
fields of properties of an instance, including element collections.
B. Only single table per class hierarchy mapping is supported with this lock type.
C. A Persistence provider will lock the entity relationships for which the locked entity
contains the foreign key.
D. A separate lock statement must be called for each subclass in entity hierarchy.