Truman's Strategy of Containment Maintained That

Truman's strategy of containment maintained that

A) it was possible to contain the expansion of communism.
B) successful direct dealings with the Soviet Union required calm and restraint.
C) successful containment of the Soviet Union would lead to a collapse of communism from within.
D) a vigilant application of counter force against the Soviet Union had to be maintained.
E) All of these