After the OPEC Oil Embargo of 1973, Western Governments, and Their

After the OPEC oil embargo of 1973, Western governments, and their people, realized that

A) oil was more important than they had thought.
B) if and when they wanted to, OPEC members could have their clients over a barrel, economically speaking.
C) they needed to develop other sources for their oil supplies, or there would be no end in sight for further price hikes.
D) much smaller countries than their own could be successful.
E) they needed to develop products that the OPEC countries needed as much as the West needed oil.