grammar - How to Highlight Words with Quotation Marks?

When we highlight words with quotation marks, should the periods and commas be within or outside of them?

Examples:

Question 1

A) He is such a "good guy."

or

B) He is such a "good guy".

Question 2

A) This smartphone is the "smartest," you should get it.

or

B) This smartphone is the "smartest", you should get it.

If possible, kindly explain why are you picking those choices.

Thank you.