Final answer:
Upon finding heavy merchandise on the floor, one should inform a manager or ask a coworker for help to ensure safety and prevent injuries.
Step-by-step explanation:
If you find heavy merchandise that has fallen on the floor from a display, the safest option to prevent any injuries or further accidents is to inform a manager of the situation (option A). If it is safe to do so, you could also ask a coworker for help (option C). Attempting to put it back without assistance (option B) could be unsafe, especially if the item is heavy or awkward to handle. It's important to assess the situation before acting; if it poses an immediate danger to others, steps should be taken to secure the area until it can be dealt with properly. Cleaning the area immediately (option D) should only be attempted if it is safe and you have the appropriate equipment and help to do so without risking personal injury.