Introduction:
The Ku band is a frequency range commonly used in satellite communication for both uplink and downlink communication. In this frequency band, different frequencies are allocated for the uplink and downlink communication.

Explanation:
What is Ku band:
The Ku band is a portion of the electromagnetic spectrum that ranges from 12 to 18 GHz. It falls between the C band and the K band. Ku band is commonly used for satellite communication due to its higher frequency range and smaller dish size requirements compared to lower-frequency bands.

Uplink and Downlink Frequencies:
The uplink frequency refers to the frequency at which signals are transmitted from the Earth station to the satellite. The downlink frequency refers to the frequency at which signals are received from the satellite by the Earth station.

Correct answer:
The correct answer is option 'D', which states that the uplink frequency is 14 GHz and the downlink frequency is 11 GHz. This means that signals are transmitted from the Earth station to the satellite at 14 GHz and received from the satellite at 11 GHz.

Reason for Correct Answer:
The uplink and downlink frequencies are allocated based on various factors such as interference, power requirements, and system design. The specific frequencies used may vary depending on the satellite communication system and the service provider. However, in the case of the Ku band, the uplink frequency is generally higher than the downlink frequency.

Conclusion:
In summary, for Ku band satellite communication, the uplink frequency is typically higher than the downlink frequency. The correct answer for the given question is option 'D', with the uplink frequency being 14 GHz and the downlink frequency being 11 GHz. It is important to note that these frequencies may vary depending on the specific satellite communication system being used.