Ans: A
$\begin{array}{cl}
& i + 2i^2+3i^3+4i^4 \\
= & i +2(-1) +3(-i) +4(1) \\
= & 2-2i
\end{array}$
$\begin{array}{cl}
& i + 2i^2+3i^3+4i^4 \\
= & i +2(-1) +3(-i) +4(1) \\
= & 2-2i
\end{array}$
Therefore, the real part is $2$.
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