Solution

Blatta orientalis is the common cockroach found in the regions of U.K. The cockroach type is also commonly called as the waterbug. During evolution, there was devolution in case of this insect. There are vestigial wings but they have loss the function of flying. The male have wings but they cannot fly. The female have vestigial wings stubs. The females never flies. This helps in identification of the different sexes.
Thus, the correct answer is option D.