To obtain very high I/P and O/P impedances in a feedback amplifier, the topology used is

ANS:B - current series

Voltage shunt means voltage sampling and shunt mixing. So in voltage sampling impedance will be reduced and in shunt mixing also impedance is reduced. In voltage shunt feedback amplifier both input and output impedance is very low.

In current series feedback amplifier both input and output impedances are very high.

So option B is the correct answer.