Which CSS selector selects the first element that is hidden or invisible?Question 9Answera.:hiddenb.:visiblec.:display-noned.:not-visible

The CSS selector that selects the first element that is hidden or invisible is a.:hidden.

Here's a step-by-step explanation:

1. CSS (Cascading Style Sheets) is a style sheet language used for describing the look and formatting of a document written in HTML or XML.

2. CSS uses selectors to target specific HTML elements and apply styles to them.

3. The ":hidden" pseudo-class selector in jQuery is used to select hidden elements.

4. In CSS, elements can be hidden in several ways, for example, by using the display property (set to none), the visibility property (set to hidden), or the opacity property (set to 0).

5. Therefore, to select the first hidden or invisible element in CSS, you would use the ":hidden" selector.

Please note that ":hidden" is not a standard CSS selector. It's a custom jQuery selector. In pure CSS, you would typically use a combination of selectors and properties to target hidden elements.