Final answer:
An interior access attic door requires a latch mechanism to ensure secure closure and prevent unintentional opening.
Step-by-step explanation:
The requirement for an interior access attic door is a latch mechanism. This mechanism ensures that the door closes securely and prevents it from opening unintentionally. It is important for both safety and to prevent the loss of heat or cooling from the living spaces below. Unlike options b, c, and d, which refer to weatherstripping, handrails, and skylights, respectively, these are not requirements for an attic access door itself. A latch is essential for creating a seal and providing secure access to the attic.