4.0.000315 $\times 7928564$ The approximate value is ( ).
(A) 210
(B) 240
(C) 2100
(D) 2400
(E) 24000
4. D.
$$
\begin{array}{l}
0.000315 \times 7928564 \\
\approx 0.0003 \times 8000000=2400
\end{array}
$$