What is a distinctive feature of cockroaches?

A distinctive feature of cockroaches is the presence of a pair of cerci at the end of the abdomen. Cerci are paired appendages that are often sensory in nature, helping cockroaches to detect changes in their environment, such as the presence of predators or obstacles. This adaptation is crucial for their survival, allowing them to respond quickly to threats.

The other characteristics mentioned in the other options, while they may apply to certain insects or arthropods, are not unique to cockroaches. For instance, the structure of the wings or body shape can vary significantly across different insect species, making them less distinctive features when specifically identifying cockroaches. The presence of cerci, however, is a notable attribute that is consistently found within this group, underscoring their role in the insects' physiology and behavior.