Problems based on Numbers Test 2

Let us assume x = 5 and y = 3 are two odd numbers and z = 2 is and even number.
Case I: ${\left(\mathit{x}-\mathit{z}\right)}^2\mathit{y}={\left(5-2\right)}^2\times 3$ $=9\times 3=27$ is odd.
Case II: ${\left(\mathit{x}-\mathit{z}\right)}^2{\mathit{y}}^2$ $={\left(5-2\right)}^2\times 3^2=9\times 9=81$ is odd.
Case III : $\left(\mathit{x}-\mathit{z}\right)\mathit{y}=\left(5-2\right)\times 3=9$ is odd.
Case IV: ${\left(\mathit{x}-\mathit{y}\right)}^2\mathit{x}={\left(5-3\right)}^2\times 2$ $=4\times 2=8$ is even.
Only the option (a) ${\left(\mathit{x}-\mathit{z}\right)}^2\mathit{y}$ is even, cannot be true.