In a GSM system, $8$ channels can co-exist in $200 \; \mathrm{kHz}$ bandwidth using TDMA. A GSM based cellular operator is allocated $5 \; \mathrm{MHz}$ bandwidth. Assuming a frequency reuse factor of $\frac{1}{5}$, i.e. a five-cell repeat pattern, the maximum number of simultaneous channels that can exist in one cell is
- $200$
- $40$
- $25$
- $5$