RC coupling

Impedance coupling

Transformer coupling

Direct coupling

impedance of choke varies with frequency

choke is quite bulky and occupies large space

expensive in comparison to RC coupling

all the above stated disadvantages

high efficiency

high power gain

low distortion

all the above stated reasons

positive half cycle of the input only

negative half cycle of the input only

entire cycle of the input

less than positive half cycle of the input

negative feedback

positive feedback

voltage feedback

current feedback