Can an HTML document validate without a DOCTYPE declaration?

No, because the validator won't know the HTML version.
No, unless it's an older version of HTML.
Yes, but only if it's an XML document.
Yes, if it uses default HTML tags.

A DOCTYPE declaration is essential for an HTML document to validate correctly. Without it, validation tools won't know which version of HTML or XHTML the document is using. Consequently, the document cannot be checked against a specific set of rules or standards. While a document might appear fine in some browsers even without a DOCTYPE, it's essential for ensuring the document adheres to web standards and is displayed consistently across all browsers.

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You're developing a FAQ section on a webpage. How would you semantically structure the questions and answers using HTML list elements?

Using
with

for questions and

for answers.
Using
1. Using
  - Using only
    tags for both.
  The
  
  tag defines a description list. Within this, the
  
  tag is used to specify the term (in this case, the question) and
  
  provides the description or definition (the answer). This ensures a semantic and structured representation of FAQs.

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Can comments in HTML contain special characters?

No, they cannot contain any special characters.
Only if they are within a CDATA section.
Yes, but they must be encoded.
Yes, except for the sequence "--".

HTML comments can contain special characters; however, they cannot include the character sequence "--" (double hyphen) as it signifies the end of the comment. Including "--" within a comment might cause the comment to terminate prematurely or result in a parsing error.

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