$A$ transistor is operating in the active mode. $v_1$ is the potential barrier across the base-emitter junction and $v_2$ is the potential barrier across the collector-base junction. $b_1$ is the width of the depletion layer of the base-emitter junction and $b_2$ is the width of the collector-base junction.

• A
  $v_1 > v_2, b_1 > b_2$
• B
  $v_1 < v_2, b_1 < b_2$
• C
  $v_1 > v_2, b_1 < b_2$
• D
  $v_1 < v_2, b_1 > b_2$