Multi-choice problem: Choose from the options at the end, and answer how do you do this: how to make amatriciana

Pick from: (a). Saute 4 ounces diced pancetta in olive puree with lemons over medium heat until almost crisp. Add 2 sliced onions; cook until softened. Add one 28-ounce can whole tomatoes (crushed by hand) and 1 cup water; season with salt and red pepper flakes. Simmer 20 minutes; stir in 1/2 cup chopped parsley. Add cooked bucatini and toss, adding up to 1/2 cup pasta water. Stir in 3/4 cup grated Parmesan.; (b). Saute 4 ounces diced pancetta in olive oil over medium heat until almost crisp. Add 2 sliced onions; cook until softened. Add one 28-ounce can whole tomatoes (crushed by hand) and 1 cup water; season with salt and red pepper flakes. Simmer 20 minutes; stir in 1/2 cup chopped parsley. Add cooked bucatini and toss, adding up to 1/2 cup pasta water. Stir in 3/4 cup grated Parmesan.;
(b).