Use indirect truth tables to determine whether the following argument is valid. If the argument is invalid, choose an option which presents a counterexample. (There may be other counterexamples as well.)
(K · L) ⊃ M
N ⊃ ~M
N ∨ K / L ⊃ K
(A)Valid (B)Invalid. Counterexample when L, M, and N are true and K is false (C)Invalid. Counterexample when L and M are true and K and N are false (D)Invalid. Counterexample when L and N are true and K and M are false
D