The following query is executed frequently against the SALES table: SELECT sales_id,
sales_date, sales_person FROM sales; If data in the SALES_ID column is unique, which
statement will create an index for optimal query performance and ensure uniqueness of the
SALES_ID column?

A.
CREATE INDEX sales_idx ON sales (sales_id, sales_date, sales_person)

B.
CREATE UNIQUE INDEX sales_idx ON sales (sales_id, sales_date, sales_person)

C.
CREATE INDEX sales_idx ON sales (sales_id) INCLUDE (sales_date, sales_person)

D.
CREATE UNIQUE INDEX sales_idx ON sales (sales_id) INCLUDE (sales_date, sales_person)

Explanation: