An electric charge \( q \) is placed at one of the corners of a cube of side \( a \). The electric qux on one of its faces will be
(a) \( \frac{q}{a \varepsilon_{0}} \)
(b) \( \frac{q}{\varepsilon_{c} a^{2}} \)
(c) \( \frac{q}{4 \pi \varepsilon_{0} a^{2}} \)
(d) \( \frac{9}{24 \varepsilon_{0}} \)