In a satellite communication, the uplink power level is generally high and power level of the received down link signal is low because:
1. High signal attenuation due to free-space loss
2. Limited available down link power
3. Finite satellite down link antenna gain, which is dictated by the required coverage area

A. 1 and 2 only

B. 1 and 3 only

C. 2 and 3 only

D. 1, 2 and 3

Answer: Option D