You are modifying a blog site to improve search engine readability.
You need to group relevant page content together to maximize search engine readability.
Which tag should you use?

A.
<article>

B.
<span>

C.
<tbody>

D.
<cd>

Explanation:
How the Changes in HTML 5 Will Affect SEO (Search Engine Optimization)?

As a SEO expert, you are most likely interested mainly in those changes in the HTML 5 specification, which will affect your work. Here is one of them:
A new <article> tag. The new <article> tag is probably the best addition from a SEO point of view. The <article> tag allows to mark separate entries in an online
publication, such as a blog or a magazine. It is expected that when articles are marked with the <article> tag, this will make the HTML code cleaner because it will
reduce the need to use <div> tags. Also, probably search engines will put more weight on the text inside the <article> tag as compared to the contents on the other
parts of the page.