CSS stands for Cascading Style Sheets. It is a style sheet language used for describing the presentation of a document written in HTML. CSS allows web designers to control the layout, colors, fonts, and other visual aspects of a webpage. It provides a way to separate the content of a webpage from its presentation, making it easier to maintain and update the design of a website.

The correct answer is

The correct answer is "h1 {background-color:#FFFFFF;}". This answer correctly uses the CSS selector "h1" to target all

elements and applies the background color property with the value of #FFFFFF, which represents white. This will add a white background color to all

elements on the webpage. The other options provided, "h1.all" and "all.h1", are not valid CSS selectors and will not apply the background color to the

elements.

The property used to change the background color is "background-color". This property allows you to specify a color value that will be applied to the background of an element. By using this property, you can easily customize the background color of a webpage or a specific element within it.

The correct HTML for referring to an external style sheet is . This code uses the element with the "rel" attribute set to "stylesheet" to indicate that it is linking to a style sheet. The "type" attribute specifies the MIME type of the linked document, in this case, text/css. The "href" attribute specifies the URL or file path of the external style sheet.

The correct place to refer to an external style sheet in an HTML document is in the

In CSS, comments are inserted using the syntax /* comment */. This allows the developer to add explanatory or descriptive notes within the CSS code without affecting the styling. The given answer correctly demonstrates the syntax for inserting a comment in a CSS file.

The correct answer is "style". The style attribute is used in HTML to define inline styles for an element. Inline styles are used to apply specific styles to individual elements, overriding any external or internal stylesheets. By using the style attribute, developers can specify CSS properties and values directly within the HTML tag, allowing for more precise control over the appearance of the element.

The correct CSS syntax is "body {color: black;}". In CSS, selectors are used to target specific HTML elements, and in this case, the "body" selector is used to target the body element of an HTML document. The curly brackets are used to enclose the declaration block, which contains the property and value pairs. In this case, the "color" property is set to "black" to specify the text color of the body element.

The correct answer is "color". The CSS property "color" is used to change the text color of an element. It allows you to specify the color of the text within the element by using a color name, a hexadecimal code, an RGB value, or other color formats supported by CSS.