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The statement $$(p \wedge (p \rightarrow q) \wedge (q \rightarrow r)) \rightarrow r$$ is
We have to inspect the compound statement $$\bigl(p \wedge (p \rightarrow q) \wedge (q \rightarrow r)\bigr) \rightarrow r$$ and decide whether it is always true (a tautology), always false (a fallacy), or equivalent to some simpler implication.
First of all, recall the standard equivalence for an implication:
$$x \rightarrow y \;\;\text{is logically equal to}\;\; \sim x \vee y.$$
Using this rule, we rewrite each implication inside the larger expression.
$$p \rightarrow q \equiv \sim p \vee q,$$
$$q \rightarrow r \equiv \sim q \vee r.$$
Substituting these into the original statement gives
$$\Bigl(p \wedge (\sim p \vee q) \wedge (\sim q \vee r)\Bigr) \rightarrow r.$$
Let us now simplify the conjunction in the antecedent, step by step.
First combine the first two factors:
$$p \wedge (\sim p \vee q) = (p \wedge \sim p) \vee (p \wedge q).$$
But $$p \wedge \sim p$$ is a contradiction, hence equal to false. So
$$(p \wedge \sim p) \vee (p \wedge q) = \text{false} \vee (p \wedge q) = p \wedge q.$$
Thus the antecedent has now become
$$(p \wedge q) \wedge (\sim q \vee r).$$
We keep going. Group the last two factors:
$$q \wedge (\sim q \vee r) = (q \wedge \sim q) \vee (q \wedge r).$$
Again $$q \wedge \sim q$$ is a contradiction, so this reduces to
$$(q \wedge \sim q) \vee (q \wedge r) = \text{false} \vee (q \wedge r) = q \wedge r.$$
Hence the whole antecedent simplifies neatly to
$$p \wedge (q \wedge r) = p \wedge q \wedge r.$$
The complete statement is therefore
$$(p \wedge q \wedge r) \rightarrow r.$$
Apply the implication equivalence once more:
$$(p \wedge q \wedge r) \rightarrow r \equiv \sim(p \wedge q \wedge r) \vee r.$$
By De Morgan’s law,
$$\sim(p \wedge q \wedge r) = \sim p \vee \sim q \vee \sim r.$$
So the entire disjunction becomes
$$\bigl(\sim p \vee \sim q \vee \sim r\bigr) \vee r.$$
Now observe that $$\sim r \vee r$$ is a tautology (it is always true). Because that tautology is one of the disjuncts, the whole expression is invariably true, no matter what truth-values $$p, q,$$ and $$r$$ may take.
Therefore the original statement is always true; that is, it is a tautology.
Hence, the correct answer is Option A.
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