Answer:
"How are we changed by war" would be considered Central idea
Explanation:
The whole book “My Mothers’ voice: The Proclamation” discusses and explains the whole idea of how people changed by war. Since the book explains around the posed question the given question is the central idea of the whole book. The other options, say Theme explains the underlying aspect but would not discuss the mentioned question. Diction or Suspense would not match the given statements. Hence, the only viable and accurate answer we have is the central idea.