What is the SQL equivalent of the following relational algebra expression?
Proj[b](Sel[a > 5](R))
Assume the existence of a relation R(a,b,c,d)
(a) Select b from R where a > 5
(b) Select a,b from R where a > 5
(c) Select a from R where b > 5
(d) Select b from R where a > (select max(b) from R)
(e) None of the above