In which of the following situations is using a subquery suitable? (refer to the tables in the JustLee Books database.) a. when you need to find all customers living in a particular region of the...

In which of the following situations is using a subquery suitable? (refer to the tables in the JustLee Books database.)
a. when you need to find all customers living in a particular region of the country
b. when you need to find all publishers who have toll-free telephone numbers
c. when you need to find the titles of all books shipped on the same date as an order
placed by a particular customer
d. when you need to find all books published by Publisher 4