Which of the following best describes the structural features of arthropods?

The best description of the structural features of arthropods is that they possess jointed appendages and a segmented body. Arthropods, which include insects, arachnids, and crustaceans, are characterized by their exoskeleton made of chitin, which provides protection and structure. The segmentation allows for specialization of different body regions for various functions, such as locomotion, feeding, and reproduction.

The jointed appendages are a defining feature that allows for a wide range of movement and adaptability in various environments. These appendages can be modified for different purposes, such as walking, jumping, grasping, or swimming, depending on the specific needs of the organism. This structural complexity contributes to the impressive diversity and survival success of arthropods across different habitats.

In contrast, options that suggest solid bodies with smooth skin, soft-bodied structures, or bilateral symmetry without legs do not accurately represent arthropods, and such descriptions would apply to other groups of organisms, showing the uniqueness of arthropod features.