Consider the following statements $A$ and $B$ and identify the correct answer given below.
$A$. Peltier coefficient is numerically equal to the potential difference across the junctions of the thermocouple through which current is flowing.
$B$. According to Thomson, energy is neither absorbed nor evolved at the junction of a thermocouple but is absorbed or evolved only along the lengths of both the conductors.

• A
  Both $A$ and $B$ are true
• B
  Both $A$ and $B$ are false
• C
  $A$ is true but $B$ is false
• D
  $A$ is false but $B$ is true