James Joyce wrote the novel Ulysses through the teens and published it in 1922, although in 1906, when he was finishing the short story collection Dubliners, he had considered the addition of another story about the canvasser Bloom, who was Jewish and who later was the title Ulysses character.
(A) he had considered the addition of another story about the canvasser Bloom, who was Jewish and who later was the title Ulysses character.
--> wrong. had.pp is not necessary and does not go along with the subordinate clause "was finishing"'s tense.
(B) he had been considering that he add an additional extra story, the Jewish canvasser Bloom, and to later make him the Ulysses' title character.
--> wrong. had.pp is not necessary and does not go along with the subordinate clause "was finishing"'s tense.
--> additional and extra have the same meaning. redundant.
(C) considering the inclusion of the story of Bloom, the Jewish canvasser who would become the Ulysses title character later
--> wrong. no subject or a verb, hence a sentence is fragmented.
(D) he considered including another story about the Jewish canvasser Bloom, who later would be the title character of the Ulysses
--> correct.
(E) he considered adding the Jewish canvasser Bloom’s story, and Bloom later would have become the Ulysses title character
--> wrong. here "would have become" suggests Bloom did not become Ulysses.