Which of the following are tautology?
(A) (P → (P ∧ Q)) → (P → Q)
(B) ((P → Q) → Q) → (P ∨ Q)
(C) ((P ∧ ¬ P) → Q) → ((P ∨ ¬ P) → R)
(D) (Q → (P ∧ ¬ P)) → (R → (P ∧ ¬ P))
Choose the correct answer from the options given below:
1
(A) Only
2
(B) Only
3
(A) and (B) Only
4
(C) and (D) Only