Which of the following commands creates a new table containing a virtual column? a. CREATE TABLE newtable

Question:

Which of the following commands creates a new table containing a virtual column?
a. CREATE TABLE newtable AS (SELECT order#, title, quantity, retail FROM orders);
b. CREATE TABLE newtable (price NUMBER(3), total NUMBER(8,2));
c. CREATE TABLE newtable (calcl NUMBER(4), calc2 NUMBER(4);
d. CREATE TABLE newtable (cola NUMBER(3), colb NUMBER(3), cole AS (cola+colb));