Answer
since $$S\left(\Xi^{-}\right)=-2,$$ $$S\left(\pi^{-}\right)=0,$$ $$S(n)=0, S\left(K^{-}\right)=-1,$$ and$$S(p)=0,$$
we have
$$-2 \neq 0+0+(-1)+0,$$
$$\text{so process does not conserve (strangeness).}$$
Work Step by Step
since $$S\left(\Xi^{-}\right)=-2,$$ $$S\left(\pi^{-}\right)=0,$$ $$S(n)=0, S\left(K^{-}\right)=-1,$$ and$$S(p)=0,$$
we have
$$-2 \neq 0+0+(-1)+0,$$
$$\text{so process does not conserve (strangeness).}$$
