Question

Which of the following tags are no longer valid in HTML5?

Answer 1

<acronym>
<applet>
<basefont>
<big>
<center>

these are few of them

Answer 2

HTML5 has no presentational attributes which are present in the HTML4 because their functions are truly better handled by the CSS.

It is essential to know that some of the attributes from HTML4 are not allowed in HTML5 at all as well as they are removed entirely.  

The tags are given below. It includes <acronym>, <applet>, <basefont>, <big> and <center>.