Explanation:

Frequency Division Duplexing (FDD) is a technique where the transmitter and receiver operate at different carrier frequencies. For instance, in mobile wireless networks, one block of spectrum is allocated for uplink, which carries data from mobile phones to a base station while another is allocated for downlink. Most cell-phone systems use FDD. The newer LTE and 4G systems use FDD. Cable TV systems are fully FDD.
The FDD technique is used in 2G/UMTS/WCDMA/LTE FDD mode within wireless networks where it powers voice and data services, and in fixed networks, it is used in asymmetric digital subscriber line (ADSL) for data services. 

Hence option 4th is correect.