How do action potentials differ from passively conducted electrical signals? Choose the correct ...

How do action potentials differ from passively conducted electrical signals? Choose the correct option.
 
  A) Action potentials diminish over distance; passively conducted signals do not diminish over distance
  B) Action potentials occur only in nerve cells; passively conducted signals occur only in muscle cells
  C) Action potentials are transmitted over short distances; passively conducted signals are conducted over long distances
  D) Action potentials are signals of fixed size and duration; passively conducted signals are not signals of fixed size and duration