A sheet or web supported by springs in a metal frame and used as a springboard

Answer – A) Trampoline

A sheet or web supported by springs in a metal frame and used as a springboard is called a trampoline. Trampolines are used for recreation and exercise, and they are also used in competitive sports such as trampolining and gymnastics.

Trampolines were invented in the early 1930s by George Nissen, a physical education instructor at the University of Southern California. Nissen was looking for a way to improve the performance of his students, and he came up with the idea of a trampoline. The first trampolines were made of canvas and were supported by metal springs. Today, trampolines are made of a variety of materials, including nylon, polyester, and fiberglass. They are also supported by a variety of materials, including metal springs, rubber bands, and elastic cords.