IN the "aging" TABLE, IF you repeatedly ACCESS customers BY account opening DATE, how can you correctly generate a multi-COLUMN INDEX USING both the Account NUMBER AND the Account opening DATE?

SELECT one:
a. CREATE INDEX customer_aging ON aging (account_number, account_opn_date) idx
b. CREATE INDEX customer_aging FROM aging (account_number,account_opn_date) TABLESPACE idx
c. CREATE INDEX customer_aging ON aging (account_number, account_opn_date) TABLESPACE idx
d. CREATE customer_aging INDEX INSIDE aging (account_number, account_opn_date) TABLESPACE idx