Which fighting position involves only one sector of fire and half of the position is dug?

The L-shaped fighting position is designed to provide effective cover and fields of fire while minimizing exposure to the enemy. This particular layout allows the shooter to cover a specific sector of fire while having the advantage of being partially covered by the terrain or fortifications dug into the ground. The 'L' shape enables the shooter to engage targets from a protected angle, and with half of the position dug out, it ensures that the armed personnel have sufficient concealment and support against enemy fire.

This type of fighting position is advantageous in battlefield scenarios where defending troops need to maintain a stable and protected point from which to engage the enemy. The layout also facilitates communication and movement within the position while restricting the exposure of personnel within it.

The other options, while they may provide certain benefits in specific situations, do not specifically meet the criteria of having only one sector of fire and half of the position being dug, which aligns perfectly with the characteristics of the L-shaped fighting position.