Final answer:
To set an image as a background in CSS, you can use the 'background-image' property for defining only the image, or the 'background' property as shorthand for setting image, position, and size. Option 1 is correct.
Step-by-step explanation:
To set an image as the background for a form or control, you can use either the background-image property or the background property in CSS. The background-image property is specifically designed to define an image as the background of an element. Here's an example of how to use it:
background-image: url('path-to-image.jg');
Please make sure that the path to the image is correct. Alternatively, the background property can be a shorthand that includes the image, position, and size properties:
background: url('path-to-image.jg') no-repeat center center / cover;
Using the background shorthand, you control not just the image but also other properties like repetition, position, and size in one declaration. The background-color property, however, is not used for images, but for setting a solid color as a background.
Hence, by using the background-image property in CSS set the background image property using an image as the background for the form or control. Option 1 is correct.