Which element is NOT necessary for form building?

In the context of form building, video embedding is not a necessary element. Form building primarily focuses on collecting user input and data through various types of fields, which can include text fields, checkboxes, radio buttons, and more. Essential aspects for effective form building include input validation rules, which ensure that the data provided by users meets specific criteria and helps maintain data integrity. Form components are the actual fields that users interact with to submit their information. Profile components may also play a role in forms where user information needs to be saved or displayed, especially in user account scenarios.

In contrast, video embedding is not a core requirement for creating functional forms. While it can enhance the user experience by providing additional context or instructions, it serves more as a supplementary feature rather than a fundamental component necessary for the form to function properly. Therefore, among the elements listed, video embedding is the one that is not essential for the primary purpose of form building, which is data collection and user interaction.