What style of writing typically emphasizes a lack of spiritual or supernatural overtones?

Naturalism is a style of writing that focuses on a realistic portrayal of life, often emphasizing the influence of environment, heredity, and social conditions on individuals. It is rooted in the belief that human behavior is determined by these external factors rather than by any spiritual or supernatural forces. This literary approach typically depicts characters from the lower, working-class strata and often highlights the darker, more brutal aspects of life, thus steering clear of idealized or romanticized elements found in other styles like Romanticism.

In contrast, Romanticism is characterized by its emphasis on emotion, nature, and individualism, often intertwining supernatural elements. Existentialism explores themes of existence, freedom, and individual choice, sometimes incorporating philosophical ideas about meaning that can include supernatural concepts. Surrealism delves into the irrational and the dream state, frequently incorporating surreal and fantastical elements.

Therefore, Naturalism stands out because it distinctly prioritizes an empirical and often bleak outlook devoid of spiritual or supernatural interpretations, making it the correct answer to the question.