Given Grammar: S->A, A->aA, A->e, B->bAWhich among the following productions are Useless productions?

Given Grammar: S->A, A->aA, A->e, B->bAWhich among the following produ

1.	Given Grammar: S->A, A->aA, A->e, B->bAWhich among the following productions are Useless productions?
A.	S->A
B.	A->aA
C.	A->e
D.	B->bA
Answer» E.