The RF amplifier A is having 3 dB NF & 5 dB of gain, amplifier B is having 3.5 dB NF & 15 dB. For overall noise figure of the cascaded system, the correct statement is:

A. A as first stage & B as second stage offers minimum over all NF

B. B as first stage & A as second stage minimum over all NF

C. Both the combination will offer same overall NF

D. Over all NF will be less than 3 dB

Answer: Option B