Assertion. The cardinality of a cartesian product can be predetermined, unlike joins.

Reason. The cardinality of a cartesian product is cardinality of table 1 x cardinality of table 2.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is not the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.

Both A and R are true and R is the correct explanation of A.

Explanation
The cardinality of a Cartesian product can be predetermined because it is the product of the cardinalities of the two participating tables, i.e., n1 * n2 where n1 and n2 are cardinalities of the two participating tables. This is unlike joins, where the cardinality depends on the specific conditions used to match the rows from the involved tables.