Consider the below CFG

G3:

S --> A

A --> B

B--> fSf| e | eSe | eSf | fSe

The language is:

a.

ALL Strings M where M is a palindrome and the middle symbol is e or f

b.

ALL Strings M where M is odd and the middle symbol is e

c.

ALL Strings M where M is even and the middle symbol is e

d.

ALL Strings M where M is a palindrome and the middle symbol is e

e.

ALL Strings M where M is even and the middle symbol is e