Which of the following is correct when using an author’s name in your essay?

Question

use the author’s full name throughout the essay
use the author’s last name when first mentioned and throughout the essay
use the author’s full name when first mentioned in your paper
use the author’s last name when first mentioned in your paper

my answer

use the author’s full name when first mentioned in your paper

Answer 1

That's correct -- and then his/her last name through the rest of the paper.