Angola's civil war happened at the time of the Cold War, when the US and Soviet Union fought a number of proxy wars. Angola's war was simialar to those and one of the sides was Marxist-Leninist, so the Soviet Union was bound to support it and the US oppose it.
C) by avoiding close interaction with other nations
<span>He was the nineteenth-century grandson of Catherine the Great, and he helped defeat Napoleon.
Hope this answers your question!!!:)</span>