58 If $\log _{2}\left[\log _{\frac{1}{2}}\left(\log _{2} x\right)\right]=\log _{3}\left[\log _{\frac{1}{3}}\left(\log _{3} y\right)\right]=\log _{5}\left[\log _{\frac{1}{5}}\left(\log _{5} z\right)\right]=0$, then the size relationship of $x$, $y, z$ is
A. $x>y>z$
B. $y>x>z$
C. $z>x>y$
D. $y>z>x$
58 B. From the problem, we know
$$
\log _{2}\left[\log _{\frac{1}{2}}\left(\log _{2} x\right)\right]=0
$$

So $x=\sqrt{2}$. Similarly, $y=\sqrt[3]{3}, z=\sqrt[3]{5}$. Therefore,
$$
\begin{array}{c}
x=\sqrt[10]{2^{5}}=\sqrt[10]{32}>\sqrt[10]{25}=\sqrt[5]{5}=z, \\
y=\sqrt[6]{9}>\sqrt[6]{8}=\sqrt{2}=x,
\end{array}
$$

Thus, we have
$$
y>x>z \text {. }
$$