Steven Parker173,522 Points
You forgot the name part, and that string is used to build a CSS selector.
The get_answer routine is called for each category of answer, and picks one at random. This string is used to select the possible choices.
For example, when the function is called for 'pet', the selector will be:
input[name="pet"]. The selector is then used to get the value of every input element from the HTML that has a name property set to "