Which affordance relates to the length of fields in forms to enhance user experience?

Field-length affordances specifically refer to how the length of input fields in forms conveys to users the expected type and amount of information they should provide. When fields are appropriately sized, they visually suggest to the user the expected input length, which can lead to a more intuitive and efficient user experience. For instance, a short field may indicate that only a small piece of information is needed, such as a first name, while a longer field might suggest that a more elaborate input like an address or a message is required.

This approach not only facilitates better input from users but also reduces frustration, as they can immediately gauge how much text is suitable for each form field. When users can understand and predict what is expected of them through the affordance of field lengths, they are more likely to successfully complete the form without unnecessary errors or confusion.

In contrast to other options, such as textual, input, or visual affordances, field-length affordances specifically address how the physical dimensions of input fields can guide user behavior and enhance the overall experience in form completion.