Given the following query, which statement is correct?
SELECT order# FROM orders
WHERE order# IN (SELECT order# FROM orderitems
WHERE isbn = '9959789321');
a. The statement doesn’t execute because the subquery and outer query don’t reference the same table.
b. The outer query removes duplicates in the subquery’s Order# list.
c. The query fails if only one result is returned to the outer query because the outer query’s WHERE clause uses the IN comparison operator.
d. No rows are displayed because the ISBN in the WHERE clause is enclosed in single quotation marks.