Given the following statements: S1: A foreign key declaration can always be replaced by an equivalent check assertion in SQL. S2: Given the table R(a, b, c) where a and b together form the primary key, the following is a valid table definition.CREATE TABLE S ( a INTEGER, d INTEGER, e INTEGER, PRIMARY KEY (d), FOREIGN KEY (a) references R)Which one of the following statements is CORRECT?

Let us analyze both statements:

• Statement S1: Foreign key constraints include referential actions such as ON DELETE CASCADE, ON UPDATE CASCADE, SET NULL, etc., which cannot be expressed using simple CHECK constraints/assertions. Furthermore, table-level CHECK constraints cannot reference columns from other tables. Hence, statement S1 is FALSE.

• Statement S2: In table $R(a, b, c)$, $(a, b)$ together form the composite primary key. In SQL, a foreign key in a referencing table must reference the entire primary key or a candidate key (with a UNIQUE constraint) of the referenced table. Referencing only a proper subset attribute a without specifying the full key $(a, b)$ is invalid. Hence, statement S2 is FALSE.

Therefore, both S1 and S2 are FALSE, making (D) the correct option.