$¬(P\leftrightarrow Q)$
$ ¬(P\rightarrow Q \wedge Q\rightarrow P)$
$¬ ((\bar{P}\vee Q) \wedge (\bar{Q}\vee P))$
$¬(\bar{P}\bar{Q} \vee PQ)$
$¬(P \odot Q)$
$(P\oplus Q)$
now check which options looks like XOR
P |
$\bar{P}$ |
Q |
$\bar{Q}$ |
$\bar{P} \leftrightarrow Q$ |
$P \leftrightarrow \bar{Q}$ |
T |
F |
T |
F |
F |
F |
T |
F |
F |
T |
T |
T |
F |
T |
T |
F |
T |
T |
F |
T |
F |
T |
F |
F |
$\bar{P} \leftrightarrow Q$ and $P \leftrightarrow \bar{Q}$ both are correct