In a satellite ground station, the received signal is directly amplified in a low noise parametric amplifier followed by a FET amplifier. The gains and effective noise temperatures of the amplifiers are 20 dB, 9.0 K and 10 dB, 200 K respectively. The effective noise temperature of the combination is

A. 11.0 K

B. 20 K

C. 29.0 K

D. 39 K

Answer: Option A