Which structure is suggested by the term "crystalline solids"?

The term "crystalline solids" refers to materials where the molecules are arranged in a highly ordered and repeating pattern, which contributes to their distinctive geometric shapes. This structured organization allows crystalline solids to exhibit unique physical properties, such as defined melting points and symmetrical shapes, which are a direct result of the way the atoms or molecules are arranged.

The structured aggregates mentioned in the correct answer highlight the orderly arrangement and well-defined structure that characterize crystalline solids, setting them apart from other states of matter. In contrast, the other options describe disordered arrangements, fluidity, or mixtures, which do not apply to the orderly nature of crystalline solids.