For transistor action

A) Base, emitter and collector regions should have similar size and doping concentrations.

B) The base region must be very thin and lightly doped.

C) The emitter-base junction is forward biased and base -collector junction is reverse biased

D) Both the emitter-base junction as well as the base-collector junction are forward biased.

• (D) and (A)

• (A) and (B)

• (B) and (C)

• (C) and (D)