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Let $$*, \square \in \{\wedge, \vee\}$$ be such that the Boolean expression $$(p * \sim q) \Rightarrow (p \square q)$$ is a tautology. Then:
We have to select the two connectives $$*$$ and $$\square$$ from the set $$\{\wedge ,\vee\}$$ in such a way that the statement
$$ (\,p * \sim q\,)\;\Rightarrow\;(p \;\square\; q) $$
is a tautology, that is, it must be true for every possible truth-value assignment of the propositional variables $$p$$ and $$q$$.
First recall the standard equivalence that rewrites an implication:
$$ a \Rightarrow b \;\equiv\; \lnot a \;\vee\; b. $$
Applying this formula to our expression we obtain
$$ (\,p * \sim q\,)\;\Rightarrow\;(p \square q) \;\equiv\; \lnot\,(p * \sim q) \;\vee\; (p \square q). $$
Because $$*$$ and $$\square$$ may each be either $$\wedge$$ (AND) or $$\vee$$ (OR), four distinct combinations are possible. We test them one by one, showing every algebraic step.
Case 1: $$*=\wedge,\;\square=\vee$$
Substituting these symbols gives
$$ \lnot\,(p \wedge \sim q) \;\vee\; (p \vee q). $$
We now push the negation inside the parenthesis with De Morgan’s law:
$$ \lnot (p \wedge \sim q) \;\equiv\; (\lnot p) \;\vee\; (\lnot\!\sim q) \;=\; (\lnot p) \;\vee\; q. $$
Therefore the whole expression becomes
$$ \big((\lnot p) \;\vee\; q\big) \;\vee\; (p \;\vee\; q). $$
Using associativity and commutativity of $$\vee$$ we group the disjuncts that involve $$p$$:
$$ \big((\lnot p) \;\vee\; p\big) \;\vee\; q. $$
Since a proposition OR its negation is always true, we have
$$ (\lnot p) \;\vee\; p \;=\; \text{T} \quad\text{(a tautology).} $$
Thus the entire expression simplifies to
$$ \text{T} \;\vee\; q \;=\; \text{T}. $$
So for $$*=\wedge,\;\square=\vee$$ the implication is always true; hence this choice makes the given statement a tautology.
Case 2: $$*=\wedge,\;\square=\wedge$$
The expression now is
$$ \lnot\,(p \wedge \sim q) \;\vee\; (p \wedge q) \;=\; (\lnot p \;\vee\; q) \;\vee\; (p \wedge q). $$
To check whether this is a tautology, take the assignment $$p=\text{T},\;q=\text{F}$$ (i.e. $$p=1,q=0$$).
Then we get
$$ \lnot p = 0,\quad q = 0,\quad p \wedge q = 1\wedge 0 = 0. $$
So the whole disjunction becomes $$0\;\vee\;0=0$$, which is false. Hence this case fails to be a tautology.
Case 3: $$*=\vee,\;\square=\vee$$
We have
$$ \lnot\,(p \vee \sim q) \;\vee\; (p \vee q). $$
Again by De Morgan,
$$ \lnot\,(p \vee \sim q) \;=\; (\lnot p) \wedge q. $$
Hence the whole statement is
$$ \big((\lnot p) \wedge q\big) \;\vee\; (p \vee q). $$
Choose $$p=\text{F},\;q=\text{F}$$. Then
$$ (\lnot p)\wedge q = 1\wedge 0 = 0,\quad p\vee q = 0\vee 0 = 0, $$
so the overall value is $$0\vee 0 = 0$$—not a tautology.
Case 4: $$*=\vee,\;\square=\wedge$$
The expression becomes
$$ \lnot\,(p \vee \sim q) \;\vee\; (p \wedge q) \;=\; ((\lnot p) \wedge q) \;\vee\; (p \wedge q). $$
With the assignment $$p=\text{F},\;q=\text{F}$$ we get
$$ (\lnot p)\wedge q = 1\wedge 0 = 0,\quad p\wedge q = 0\wedge 0 = 0, $$
so the disjunction is again $$0\vee 0 = 0$$. Hence this case also fails to be a tautology.
Among all four possibilities, only Case 1—namely $$*=\wedge$$ and $$\square=\vee$$—produces a statement that is true under every possible truth assignment. All other choices admit at least one counter-example, so they are not tautologies.
Hence, the correct answer is Option C.
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