Which sensing term indicates a high level of uncertainty about a target?

The term that indicates a high level of uncertainty about a target is "Doubtful." In military and tactical contexts, uncertainty in identifying or tracking a target is critical, as it affects decision-making and the ability to engage effectively. When a target is described as doubtful, it conveys that there is significant hesitance or ambiguity regarding its identification, status, or location. This term underscores the need for further reconnaissance or verification before taking action.

The other options suggest different levels of situational awareness or different conditions. "Short" typically refers to a limited range of detection or a brief time frame, which does not necessarily indicate uncertainty about a target. "Lost" implies complete loss of visual or sensor contact with a target, indicating a lack of information but not specifically a high level of uncertainty about a previously identified target. "Over" is often used in communications to signal the end of a transmission, rather than to describe uncertainty. Thus, "Doubtful" is the most appropriate term to represent high uncertainty regarding a target's status.