Which of the following is NOT a tautology?
Source: Cracking the Mathematics GRE, Princeton Review..
I would think the answer is option C AND E?
C is wrong since
would produce a true value for the "left-hand side" while producing a false value for the 'right hand side'
E is also wrong since
would produce the necessary counterexample.
Is there anything wrong with my above reasoning?
I am very confused by the book's answer: Finally, choice (E) is the Distributive Property for sentential logic (clearly wrong??), so the statement is always true regardless of the values of sentences A, B, and C.