An amplifier has a midband power gain of 24，500.What is the value of the power gain in dB for the circuit？（）

An amplifier has a midband power gain of 24，500.What is the value of the power gain in dB for the circuit？（）
A.87.78 dB
B.43.9 dB
C.4.39 dB
正确答案：43.9 dB