What range refinement is needed if the registration point is nearer the last rounds fired?

When considering range refinement in the context of artillery or fire support coordination, a registration point that is closer to the last rounds fired typically indicates that the initial rounds have already accurately established the vicinity of the target. If the registration point is indeed near the last rounds fired, this suggests that the previously obtained data is reliable and the rounds should be effective in hitting the intended target without any additional adjustments.

Therefore, the correct choice indicates that no further range refinement is necessary in this situation. This reflects the principle that if the data is already validated and the registration point is close to where previous munitions landed, the existing information can be used directly for subsequent fire missions. This approach minimizes the risk of unnecessary adjustments that could lead to confusion or misfires.

In scenarios where the registration point varies significantly from the last rounds, or if multiple adjustments are needed, greater refinements might be required, making the other options less applicable.