A Junction in a Photovoltaic (Solar) Cell Is Which of the Following

A junction in a photovoltaic (solar) cell is which of the following?

A) a thin layer of n-type semiconductor in contact with a p-type semiconductor
B) three pieces of semiconductor that form a p-n-p connection
C) wires that carry electricity that are attached to the cell
D) pure germanium that is attached to a p-type semiconductor
E) a thin layer of p-type semiconductor in contact with an n-type semiconductor