The correct option is A Linguatula
Pentastomida is a group of parasitic invertebrates. These are obligate parasites. These organisms are commonly known as tongue worms. There is resemblance of the organism to the species of the genus Linguatula to the vertebrate tongue. The organisms are called as Pentastoma which refers to five openings. There is only one mouth out of all these openings.
Thus, the correct answer is option A.