Which formula shows the arrangement of atoms and bonds within a molecule?

The structural formula is the correct choice because it provides a detailed representation of the arrangement of atoms and the types of bonds between them within a molecule. This formula conveys not only the composition of the molecule—in terms of which atoms are present and in what quantities—but also how these atoms are connected to each other, including information about bond types (single, double, etc.) and the spatial arrangement of atoms.

In contrast, the empirical formula only gives the simplest integer ratio of the different types of atoms in a molecule without indicating how they are arranged or bonded. The molecular formula focuses on the number of each type of atom present, but it does not provide any detail about connectivity or structural information. The atomic formula is not a standard term used in chemistry to describe molecular structures, so it does not apply here.