Consider the following two statements $A$ and $B$,and identify the correct choice out of the given answers:
$A$. Thermo $e.m.f.$ is minimum at the neutral temperature of a thermocouple.
$B$. When two junctions made of two different metallic wires are maintained at different temperatures,an electric current is generated in the circuit.

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