Premise: Tomato sauce (also known as Neapolitan sauce, and referred to in Italy as Salsa di pomodoro) refers to any of a very large number of sauces made primarily from tomatoes, usually to be served as part of a dish (rather than as a condiment). Tomato sauces are common for meat and vegetables, but they are perhaps best known as sauces for pasta dishes.
Hypothesis: Neapolitan sauce, tomato sauce and Salsa di pomodoro are all the same thing.