Which playwright is associated with both naturalism and realism?

The playwright associated with both naturalism and realism is Henrik Ibsen, who is sometimes confused with other playwrights. However, if focusing on the given choices, the most fitting option is Henry Becque. He was a French playwright who contributed to the development of naturalism and realism in theatre, particularly through his works that emphasized the complexity of human experience and social issues. His writing style often incorporated an objective portrayal of characters and scenarios, reflecting the principles of these movements.

Other playwrights listed do have their own significance in literature, but they are not primarily credited with the dual contribution to both naturalism and realism. Honore de Balzac is primarily known for his realist novels, Giovanni Verga is associated mainly with realism in literary techniques, and J.M. Barrie is known for his whimsical and fantastical plays, which do not align with the principles of naturalism.

Thus, Henry Becque stands out as the playwright most clearly linked to both naturalism and realism, making this the correct choice in the context of this question.