Final answer:
Unused openings in a box or cabinet must be effectively closed to protect the contents inside.
Step-by-step explanation:
The statement 'Unused openings in a box or cabinet must be effectively closed' is true.
When it comes to storing items in a box or cabinet, it is important to effectively close any unused openings to prevent dust, pests, or other unwanted items from entering. By effectively closing these openings, you can keep the contents of the box or cabinet protected and maintain their quality.
An example of effectively closing unused openings is using lids, doors, or covers to seal off any gaps or holes in a box or cabinet. Additionally, using sealing materials such as tapes, caulk, or weatherstripping can further ensure that the openings are tightly closed.