For a short period in the 1950s, Iran nationalized its oil industry because the original concession agreement with the British had expired. It was taken over by a communist government. Which of the following options explains why Iran decided to nationalize its oil industry?

A) The original concession agreement had expired.
B) Iran wanted to assert control over its resources.
C) The British were not meeting their obligations.
D) The communist government wanted to gain more power.