What seafood delicacy is traditionally served atop crackers with sour cream and chopped onions?

Caviar

Who’s the narrator (character) at the start of Disney's "Aladdin"? Who is credited with inventing the first practical telephone? Which President coined the phrase "military-industrial complex" in a farewell speech? Which country is called the Emerald Isle? Which game is set in Aperture Science laboratories where players undergo testing?