What are the things that you should remember in getting a secondary source?

A. created by an educated expert and published in an academic journal ...

B. a firsthand account published in a magazine ...

C. written by a student and posted to his individual website ...

D. creatively written and published on a blog ...

You should remember A

When getting a secondary source one thing to remember is it can be created by an educated expert and published in an academic journal. Also, a firsthand account published in a magazine will also work as a secondary source. So bother A and B will be correct. If only one can be chosen, A would be the better of the two.