The line formation is best utilized when what two conditions are present?

The selection of the correct answer is based on the unique characteristics of line formations in military tactics. This formation excels in scenarios where there is a low probability of enemy contact and a pressing need for efficiency in movement.

When no enemy contact is expected, the line formation allows for maximum visibility and coverage of the surroundings, enabling personnel to move quickly and efficiently without the need for extensive tactical positioning or concealment. This is particularly important in situations where time is critical, as the formation can facilitate rapid movement through an area, ensuring units can reach their destination quicker than they might in other, more cautious formations. The emphasis here is on speed and efficiency rather than stealth or defensive positioning, which aligns perfectly with the parameters of the question.

Other scenarios typically require different formations, suited for situations where threats are imminent or where stealth and terrain considerations become paramount, hence influencing the effective use of various tactical configurations.