It is a declarative sentence as it is making a statement.
Interrogative- question (?)
Imperative- request/order/advice
Exclamatory- surprise (!)
Declarative- simple statement
Italics do not show up on this site, but "D. Have you read Ambrose Bierce's short story An Occurence at Owl Creek Bridge" works as long as "An Occurence at Owl Creek Bridge" is in italics.
I believe it is B) dialogue.