If the domain of the function $f(x) = \frac{[x]}{1+x^2}$, where $[x]$ is greatest integer $\leq x$, is $[2,6)$, then its range is:
\( \left( \dfrac{5}{37}, \dfrac{2}{5} \right] - \left\{ \dfrac{9}{29}, \dfrac{27}{109}, \dfrac{18}{89}, \dfrac{9}{53} \right\} \)
\( \left( \dfrac{5}{26}, \dfrac{2}{5} \right] - \left\{ \dfrac{9}{29}, \dfrac{27}{109}, \dfrac{18}{89}, \dfrac{9}{53} \right\} \)
\( \left( \dfrac{5}{37}, \dfrac{2}{5} \right] \)
\( \left( \dfrac{5}{26}, \dfrac{2}{5} \right] \)