Position 3 places a security personnel in what disadvantageous situation for the subject?

Positioning security personnel in a manner where the subject is facing the opposite direction creates a substantial disadvantage. When a subject is facing away, they have the opportunity to react in unexpected ways without the security personnel's awareness. This could mean they can escape, attack, or perform another action without being seen.

In contrast, if personnel are positioned such that they can see and face the subject directly, they maintain better situational awareness and can anticipate the subject’s movements. Maintaining eye contact or positioning oneself in a way that limits the subject’s ability to act unobserved is critical in security situations to ensure control over the environment and minimize risks.

The other options highlight different aspects of vulnerability but do not capture the specific disadvantage that comes from the subject unexpectedly being able to maneuver or react without the security personnel being prepared to respond appropriately.