Question

what is one central idea of nurse and spy in the union army?
being forced to violate an oath one has taken can be devastating
having to make important decisions under pressure leads to mistakes.
finding ones way out of difficult situations takes cunning and bravery.
no person should be forced to fight in a war

Explanation:

In "Nurse and Spy in the Union Army", the protagonist navigates complex and dangerous scenarios as a nurse and spy. This requires both clever - ness (cunning) and courage (bravery), making this option the most fitting central idea among the choices.

Answer:

Finding one's way out of difficult situations takes cunning and bravery.