Answer: D. standard English
Step-by-step explanation:
Standard English is used in formal settings, such as is literature like the excerpt presented in this question, as opposed to non-standard English which is used in informal settings, with family and friends.
Although Standard English began as a regional dialect that emerged in the southeast of England, is now considered the official form to be used in writing, in the education system, court texts, the church, newspapers, and any official writing, and it can be used with different regional accents or without any regional diction.
We know that the excerpt is no using a southern dialect because there are no words like "ain’t" and "y’all", which are common for that dialect.