How is terrain leveraged for observation and fields of fire in defense?

How is terrain leveraged for observation and fields of fire in defense?

• A. Avoid elevated positions to minimize detection.
• B. Disperse forces without mutual support to reduce visibility.
• C. Ignore natural cover to maximize visibility.
• D. Place positions on high ground, use natural cover, align fields of fire to cover avenues of approach, ensure mutual support.

Answer: (D)