Introduction:
WiMAX (Worldwide Interoperability for Microwave Access) is a wireless communication technology that provides high-speed internet access over long distances. It is based on the IEEE 802.16 standard and uses a variety of modulation techniques to achieve its goals.

Full Duplex Communication:
The correct answer is option 'C' - WiMAX provides full duplex communication. Full duplex communication refers to the ability of a communication system to transmit and receive data simultaneously. In other words, it allows for two-way communication where both parties can send and receive data at the same time.

Explanation:
WiMAX is designed to provide high-speed internet access to users over a wide area, similar to Wi-Fi but with a much larger coverage area. It uses a combination of microwave and OFDM (Orthogonal Frequency Division Multiplexing) technologies to achieve high data rates and long-range connectivity.

WiMAX operates in different frequency bands, including licensed and unlicensed bands. It can support both line-of-sight (LOS) and non-line-of-sight (NLOS) deployments, making it suitable for various environments.

Key Features of WiMAX:
1. Multiple Access Techniques: WiMAX supports multiple access techniques such as Time Division Multiple Access (TDMA) and Frequency Division Multiple Access (FDMA) to efficiently allocate resources and provide optimal bandwidth utilization.
2. Scalability: WiMAX can support a large number of users simultaneously, making it suitable for densely populated areas.
3. Quality of Service (QoS): WiMAX provides QoS mechanisms to prioritize different types of traffic, ensuring that real-time applications such as voice and video receive the necessary bandwidth and latency requirements.
4. Security: WiMAX incorporates various security features such as encryption and authentication to protect data transmitted over the network.
5. Mobility: WiMAX supports mobility, allowing users to maintain connectivity while moving at high speeds, such as in vehicles or trains.

Conclusion:
WiMAX provides full duplex communication, allowing for simultaneous transmission and reception of data. It offers high-speed internet access over long distances and supports various features such as scalability, QoS, security, and mobility. WiMAX has been widely used in both urban and rural areas to bridge the digital divide and provide broadband connectivity to underserved regions.