In CSS, a rule is composed of a selector and a declaration block. The rule is the entire part that defines how styles should be applied to elements matching the selector.
* CSS Rule Components:
* Selector: Identifies the HTML elements to be styled (e.g., body, .name, #item).
* Declaration Block: Contains one or more declarations, each consisting of a property and a value, enclosed in curly braces {}.
* Example Analysis:
* Option A:
body {
background-color: white;
}
This is the full rule, consisting of the selector body and the declaration block { background-color: white; }.
* Option B:
background-color: white;
This is just a declaration, not a complete rule.
background-color: white,
This is an incorrect declaration due to the comma, and not a complete rule.
* Option D:
color: black
This is just a declaration, not a complete rule.
* References:
* W3C CSS Syntax and Basic Data Types Module Level 3
* MDN Web Docs - CSS Syntax