How will all movements be made within the form B limits when authority limits overlap?

The correct choice emphasizes that all movements within the Form B limits, especially when authority limits overlap, must be conducted under the direction of the employee in charge of the track bulletin Form B. This ensures that there is a clear line of authority and communication regarding the safe operations over the protected track sections.

In situations where authority limits overlap, having a single point of control—namely the employee in charge—helps manage complexity and minimize the risk of accidents or misunderstandings. This individual is responsible for coordinating the movements and ensuring that safety protocols are strictly followed.

The other options suggest various forms of independent or unaided actions which could lead to miscommunication or unsafe conditions. Individual movements without direction may lead to confusion, and reliance solely on posted signals does not account for real-time situational awareness. Notifying the dispatcher is also important, but it does not replace the necessity of operating under the direct supervision of the designated employee in charge when navigating overlapping authority limits. Thus, the emphasis on following the direction of the employee in charge is integral to maintaining safety and order in these situations.