Although Considered to Be a Strong Point, Why Was Germany's

Although considered to be a strong point, why was Germany's alliance system a problem?

A) Bismarck's Reinsurance Treaty was renewed by Wilhelm II.
B) Although an ally, Russia turned to Austria for an alliance.
C) The pact with Austria broke down, as Hungary won its independence.
D) It pushed England and France into an alliance.
E) Germany's Triple Alliance involved nations that wanted German colonies in Africa.