Answer: B. Many psychological horror stories.
Explanation: in literature, parallelism is the use of elements that are the same grammatically, or have similar sound, construction or meter. It is used to give the sentence a sense of rhythm. In the given sentence we can see that the structure of the listed genres is just the genre without any pronoun or verb (poetry, detective fiction) so in order to be a sentence with parallel structure, the continuation of the sentences must have the same structure, which correspond to option B: "Edgar Allan Poe wrote poetry, detective fiction, and many psychological horror stories."
