Which tag adds a horizontal line separating elements from the top?
<h1>
<line>
<row>
<hr>
<hr>
The correct tag that adds a horizontal line separating elements from the top is the "<hr>" tag.
The correct tag to add a horizontal line separating elements from the top is <hr>.
To add a horizontal line using the <hr> tag, simply include the <hr> tag in your HTML code where you want the line to be placed. For example:
```html
<h1>This is a heading</h1>
<hr>
<p>This is some text.</p>
```
In this example, a horizontal line will be displayed between the heading and the paragraph.
The <hr> tag is a self-closing tag, meaning it does not require a closing tag. It is also considered a void element, which means it does not have any content or attributes.
Note that the appearance of the horizontal line may vary depending on the browser and default styling. You can further customize the appearance of the <hr> tag using CSS if desired.