The background-color property in CSS is used to specify the background color of an element. The background covers the total size of the element with padding and border but excluding margin.

Explanation:

The correct answer is option 'C' - background-color.

Background-color Property in CSS:
The background-color property in CSS is used to change the background color of an element on a webpage. It specifies the color of the background area behind the content of an element. By setting a specific color value for the background, you can enhance the visual appearance of your webpage and make it more appealing to the users.

Usage:
To use the background-color property in CSS, you need to specify the color value you want to apply. This can be done in various ways:

1. Using color names: You can specify a color by using predefined color names such as "red", "blue", "green", etc. For example:


2. Using hexadecimal values: Hexadecimal values are commonly used to represent colors in web design. You can specify a color by using a six-digit hexadecimal value preceded by a hash (#) symbol. For example:


3. Using RGB values: RGB (Red, Green, Blue) values can also be used to specify a color. Each color component is represented by a number ranging from 0 to 255. For example:


4. Using RGBA values: RGBA (Red, Green, Blue, Alpha) values are similar to RGB values but with an additional alpha channel. The alpha channel represents the transparency of the color. The value ranges from 0 (completely transparent) to 1 (completely opaque). For example:


Conclusion:
The background-color property is a versatile CSS property that allows you to change the background color of an element on a webpage. By specifying a color value, you can enhance the visual appearance of your webpage and make it more visually appealing to the users.