A. the use of rowid
B. a GROUP BY clause
C. an ORDER BY clause
D. only an inline view
E. an inline view and an outer query

A. SELECT TOTAL(*)   FROM customers;
B. SELECT COUNT(*)   FROM customers;
C. SELECT TOTAL(customer_id)   FROM customers;
D. SELECT COUNT(customer_id)   FROM customers;
E. SELECT COUNT(customers)   FROM customers;
F. SELECT TOTAL(customer_name)   FROM customers;