The View Source feature in browsers allows users to see the raw HTML source code of a webpage. Even if content is commented out using HTML comment tags, it is still visible in the source. This is a key consideration for developers to ensure sensitive information is not left in comments. 

In HTML, comments are wrapped between . These delimiters instruct the browser to ignore everything between them. It's important to note that unlike comments in some other languages, HTML comments are visible in the source code but won't be displayed in the rendered page. 

The shape attribute in the

tag is used to define the shape of the clickable area in an image map. The possible values can be "rect" (rectangle), "circle", "poly" (polygon), and "default". This attribute, in conjunction with the coords attribute, enables different areas of an image to be linked to different destinations. 

The line-height property in CSS determines the amount of space above and below inline elements. It's typically used to improve the readability of text, especially in larger blocks. The value can be a number, length, or a percentage. When used correctly, line-height can enhance the visual appeal of text on a webpage. 

Using appropriate heading tags (h1 through h6) in HTML provides a structured hierarchy to your content, making it more readable for both users and search engines. This structure helps search engines understand the importance and context of the content, which can contribute positively to search engine rankings. Proper use of headings can enhance content discoverability and accessibility, thus playing a crucial role in SEO. 

Commented out code doesn't execute or affect rendering. If a script tag is commented out, any functionality provided by that script will be unavailable. To truly understand its effect, one would need to uncomment it and observe potential behavioral changes on the webpage. 

The multiple attribute can be added to the element to allow users to select multiple options from the dropdown list. When set, users can typically hold down the Ctrl (or Cmd on Mac) button while clicking to select multiple options. 

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The "action" attribute in the form element specifies the ______ to which the form data is sent.

Difficulty level

• URL 
• element 
• enctype 
• method 

The "action" attribute in the form element defines the URL where the form data should be sent after submission. It can be an absolute or relative URL. The server at that URL then processes the form data, often saving it or sending an email, depending on the back-end logic. 

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Which attribute of the form element specifies where to send the form-data when the form is submitted?

Difficulty level

• action 
• destination 
• submit-to 
• target 

The action attribute of the form element defines the URL (or URI) where the form data should be sent after submission. This can be a URL of a server-side script (like PHP, Python, etc.) that processes the form data and sends a response back to the user. The choice of where to send the data is crucial as it determines how the data will be processed and handled on the server side. 

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The _____ and _____ tags are used to create and describe terms in a description list, respectively.

Difficulty level

• &  
• &

   
• &  
• &  

In HTML, a description list is represented using the

tag. Within this list, the

tag is used to denote the term, and the

tag is used for the corresponding description. Description lists are useful for things like glossaries or key-value pairs. 

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