Final answer:
The 'for' attribute in a tag associates the label with a form element by matching the 'for' attribute with the id of the form element. It does not discriminate between types of form elements.
Step-by-step explanation:
The 'for' attribute in a <label> tag is used to associate the label with a particular form element. It does this by matching the 'for' attribute to the id of a form element. This means that when you choose an option like '4) Defines the form element to which the label belongs' you are largely correct. However, while it can specify the label for a checkbox or radio button it can be used with other form elements as well such as text inputs, not just checkboxes and radio buttons. It doesn't inherently discriminate between different types of form elements.
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