Name one source where Soldiers can find study material for promotion boards.

The choice of Army Study Guides as a source for finding study material for promotion boards is appropriate because these guides are specifically designed to assist soldiers in preparing for various aspects of military life, including promotions. Army Study Guides often include comprehensive information tailored to the promotion board process, covering subjects such as Army regulations, leadership principles, and other essential knowledge required for advancement.

These guides are particularly valuable as they are generally curated by experienced personnel who understand what is relevant and necessary for soldiers aiming to succeed during their promotion boards, making them a focused and effective resource for study preparation.