The Q factor, also known as the quality factor, is a measure of the sharpness or selectivity of a resonant circuit. It is defined as the ratio of the resonant frequency (fr) to the bandwidth (BW) of the circuit.

Q factor = fr / BW

Given that the resonant frequency (fr) of the RF amplifier is 1 MHz and the bandwidth (BW) is 10 kHz, we can calculate the Q factor as follows:

Q factor = 1 MHz / 10 kHz = 100

Therefore, the correct answer is option 'B', which states that the Q factor is 100.

Explanation:
The resonant frequency is the frequency at which the circuit exhibits maximum response or resonance. In this case, the resonant frequency of the RF amplifier is given as 1 MHz.

The bandwidth, on the other hand, is the range of frequencies over which the circuit operates effectively. It is the difference between the upper and lower cut-off frequencies. In this case, the bandwidth of the RF amplifier is given as 10 kHz.

The Q factor is a measure of how sharply the circuit can discriminate between frequencies. A higher Q factor indicates a sharper or narrower resonance, while a lower Q factor indicates a broader resonance.

In this case, the Q factor is calculated by dividing the resonant frequency by the bandwidth. Substituting the given values:

Q factor = 1 MHz / 10 kHz = 100

Therefore, the Q factor of the RF amplifier is 100, as stated in option 'B'. This indicates that the amplifier has a sharp resonance and a narrow bandwidth.