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We need to identify which of the given statements is a tautology (always true regardless of truth values of $$p$$ and $$q$$).
Analyze Option A: $$((\sim q) \wedge p) \wedge q$$
This simplifies to $$p \wedge q \wedge (\sim q)$$, which contains $$q \wedge (\sim q) = F$$.
So this is always False (contradiction). Not a tautology.
Analyze Option B: $$((\sim q) \wedge p) \wedge (p \wedge (\sim p))$$
The term $$p \wedge (\sim p) = F$$.
So the entire expression is $$(\text{anything}) \wedge F = F$$.
This is always False (contradiction). Not a tautology.
Analyze Option C: $$((\sim q) \wedge p) \vee (p \vee (\sim p))$$
The term $$p \vee (\sim p) = T$$ (this is a tautology by itself).
So the entire expression is $$(\text{anything}) \vee T = T$$.
This is always True. This is a tautology!
Analyze Option D: $$(p \wedge q) \wedge (\sim(p \wedge q))$$
Let $$r = p \wedge q$$. Then this becomes $$r \wedge (\sim r) = F$$.
This is always False (contradiction). Not a tautology.
Therefore, the tautology is Option C: $$((\sim q) \wedge p) \vee (p \vee (\sim p))$$.
The correct answer is Option C.
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