3. The number of positive simplest proper fractions with a denominator of 2007 is ( ).
(A) 675
(B) 1326
(C) 1329
(D) 1332
3. D.

Since $2007=3^{2} \times 223$, the number of positive integers less than 2007 and coprime with 2007 is
$$
\begin{array}{l}
2007-\left[\frac{2007}{3}\right]-\left[\frac{2007}{223}\right]+\left[\frac{2007}{3 \times 223}\right] \\
=1332 \text { (numbers). }
\end{array}
$$