Which operator is equivalent to (P ⟹ Q)∧(Q ⟹ P)(P \implies Q) \land (Q \implies P)(P⟹Q)∧(Q⟹P)?
P⊕QP \oplus QP⊕Q
P↔QP \leftrightarrow QP↔Q
P↑QP \uparrow QP↑Q
P↓QP \downarrow QP↓Q