While executing a CFF, what spotting would you make if you received a Splash call and after waiting 5 seconds you neither see nor hear the round impact?

The correct answer is that "Lost" is the appropriate spotting to make when you receive a Splash call and, after waiting five seconds, you neither see nor hear the round impact. This term indicates that the observer has lost track of the projectile's path, which can happen due to several factors such as low visibility, noise interference, or other environmental conditions that prevent tracking.

In this context, "Lost" highlights the situation where it's unclear whether the round has impacted correctly or if there was a failure in the delivery of the round itself. Spotting as "Lost" is crucial because it informs the firing unit that the observer cannot provide accurate corrections based on the impact, and further communication may be necessary to determine the next steps.

The other options, while related to spotting, do not correctly capture the situation of losing track of the ordinance. "Doubtful" generally conveys uncertainty about whether the round was effective or not, but in this case, the observer has definitively lost visual or auditory contact with the rounds. "Unobserved" implies that the rounds were fired but could not be tracked, yet would not necessarily communicate that the observer lost the track after the Splash call. "Cannot Observe" might suggest that conditions prevent observation entirely, which