Which set of form elements permits the selection of only one item from a group?

The correct answer involves using a radio button element, which is designed specifically for allowing users to select only one option from a group. When multiple radio buttons are grouped under the same name attribute, selecting one radio button automatically deselects any previously selected button in that group. This behavior enforces the restriction that only one item can be selected at any given time, making it the ideal choice for scenarios where a singular selection is necessary.

In contrast, the other options represent different types of form elements that do not restrict selections in the same manner. A checkbox, for example, allows users to select multiple items; hence, it doesn’t enforce a single choice. The multiple attribute in a select element permits users to choose several options simultaneously, which defeats the purpose of having only one selection. The input type number allows for numerical input but does not provide any selection functionality at all.

Thus, using the radio button is the appropriate choice for situations where only a single selection is permitted from a defined set of options.