8. The sequence $\left\{D_{n}\right\}$ satisfies:
$$
\begin{array}{l}
D_{0}=D_{1}=0, D_{2}=1, \\
D_{n}=D_{n-1}+D_{n-3}(n \geqslant 3) .
\end{array}
$$

Then the parity of $\left(D_{2021}, D_{2022}, D_{2023}\right)$ is ( ).
(A) (odd, even, odd)
(B) (even, even, odd)
(C) (even, odd, even)
(D) (odd, odd, even)
(E) (odd, odd, odd)
8. C.
$D_{n}(n=1,2, \cdots, 11)$ values are shown in Table 1.
Table 1
\begin{tabular}{cccccccccccc}
$D_{0}$ & $D_{1}$ & $D_{2}$ & $D_{3}$ & $D_{4}$ & $D_{5}$ & $D_{6}$ & $D_{7}$ & $D_{8}$ & $D_{9}$ & $D_{10}$ & $D_{11}$ \\
\hline 0 & 0 & 1 & 1 & 1 & 2 & 3 & 4 & 6 & 9 & 13 & 19 \\
\hline & & & & & & & & & & & \\
\hline
\end{tabular}

Even Even Odd Odd Odd Even Odd Even Even Odd Odd From Table 1, we know the period $T=7$.
Thus, $D_{2021}=D_{5}=2$ (even),
$D_{2022}=D_{6}=3$ (odd),
$D_{2023}=D_{7}$ (even).