33. There is an arithmetic sequence with 100 terms and a common difference of 4, the sum of which is 20300. Then the first term of this sequence is ().
(A) 1
(B) 2
(C) 3
(D) 4
$(\mathrm{E}) *$
33. (E).

Let the first term be $a_{1}$. Then $a_{100}=a_{1}+99 \times 4$.
$$
\begin{array}{c}
\text { Also } S_{\mathrm{H \omega}}=100 \cdot \frac{a_{1}+a_{100}}{2}=20300 \\
\Rightarrow a_{1}+99 \times 2=203 \Rightarrow a_{1}=5 .
\end{array}
$$