I believe the answer is 2, but I am not entirely sure why. Please explain. The last person gave the answer but did not explain why.
Consider the language PALINDROME or ODD. We will use the pumping lemma to prove it is not regular and pump on w = a^n bba. What values of i will work to pump out of the language? Reminder: since the first n symbols are all a's, we must have y = a^j and i is the number of times we loop or pump on y.
i) i = 0
ii) i = 1
iii) i = 2
iv) i = 3
Exactly 3 of them
Exactly 1 of them
Exactly 2 of them
All 4 of them