4. (4 points) Read from Figure 2: Turing Machine 2 the description of Turing machine and select the option under which the Turing machine accepts the input string Here is a description of a Turing machine. The input alphabet is [a, b). The state set is: The transition function is given in the table below: 40 la Ab acb gleft a (Ga. , R) (a, a, R) (b, a, R) t L) (rej , R) (liet, a, L) Figure 2: Turing Machine 2 A. Incomplete information and answer cannot be found. B. The Turing machine accepts on input x if and only if x is a reverse. C. The Turing machine accepts on input x if and only if the first and last char acters in x are the same D. The Turing machine accepts on input x if and only if x is a palindrome E. None of the above