Final answer:
People commonly hang metal Christmas ornaments on their Christmas trees. These can include bells, stars, and decorative metal spheres, contributing to the festive decoration of the holiday season.
Step-by-step explanation:
The metal item commonly hung on Christmas trees is known as a Christmas ornament. These ornaments can come in various shapes, sizes, and materials, including metal, glass, wood, and plastic. However, when specifically referring to metal items, people often hang ornaments that can be metal bells, stars, or even intricately designed metal spheres.
These items are a staple of traditional Christmas décor and serve to enhance the festive atmosphere during the holiday season. Over time, Christmas tree ornaments have evolved to include a wide array of designs, from classic to modern, and often are chosen to fit a particular theme or color scheme.