$26 \cdot 8$ A circle with an inscribed square and a circumscribed square has its center at the origin $O$ of a rectangular coordinate system with $x$-axis $O x$ and $y$-axis $O y$, as shown in the figures $\mathrm{I}$ to $\mathrm{N}$ below. The geometric meaning of the inequality $|x|+|y| \leqslant \sqrt{2\left(x^{2}+y^{2}\right)} \leqslant 2 \max (|x|,|y|)$ is represented by the figure
(A) I.
(B) $I I$.
(C) III.
(D) IV.
(E) None of the above.
(24th American High School Mathematics Examination, 1973)