Right option is (a) 5 MHz
For explanation I would say: W-CDMA/UMTS requires a minimum spectrum allocation of 5 MHz. Using this bandwidth, it has the capacity to carry over 100 simultaneous voice calls. It is able to carry data at speeds up to 2 Mbps in its original format. 20 MHz is the bandwidth defined for LTE. CdmaOne uses a bandwidth of 1.25 MHz. GSM’s bandwidth is 200 KHz.