Which property is used to change the background color of an element in CSS?

The property that is used to change the background color of an element in CSS is the background-color property. This property allows developers to specify a color that fills the background area of an element, whether it be a div, a section, or any other container. By using this property, you can create visual separation between elements, highlight certain sections, or improve overall design aesthetics by applying various colors.

The background-color property accepts various values, including named colors, hex codes, RGB, RGBA, HSL, and HSLA, providing a flexible approach to styling web pages. This versatility makes it essential for creating engaging web designs.

Other options do not serve the purpose of changing the background color. The color property refers to the text color, bgcolor is an outdated attribute primarily used in HTML, and fill is typically associated with SVG elements to change the color of shapes within graphics, rather than affecting the background of HTML elements. Thus, background-color stands out as the correct choice for this purpose.