Question: Fenbendazole is ineffective against which parasite that is also called the flea tapeworm?

Context paragraphs:
Trypanosoma brucei: Trypanosoma brucei is a species of parasitic kinetoplastid belonging to the genus "Trypanosoma".  The parasite is the cause of a vector-borne disease of vertebrate animals, including humans, carried by genera of tsetse fly in sub-Saharan Africa.  In humans "T. brucei" causes African trypanosomiasis, or sleeping sickness.  In animals it causes animal trypanosomiasis, also called nagana in cattle and horses.  "T. brucei" has traditionally been grouped into three subspecies: "T. b. brucei", "T. b. gambiense" and "T. b. rhodesiense".  The first is a parasite of non-human vertebrates, while the latter two are the known parasites of humans.  Only rarely can the "T. b. brucei" infect a human.

Biological agent: A biological agent—also called bio-agent, biological threat agent, biological warfare agent, biological weapon, or bioweapon—is a bacterium, virus, protozoan, parasite, or fungus that can be used purposefully as a weapon in bioterrorism or biological warfare (BW).  In addition to these living and/or replicating pathogens, biological toxins are also included among the bio-agents.  More than 1,200 different kinds of potentially weaponizable bio-agents have been described and studied to date.

Fenbendazole: Fenbendazole (Hoechst brand names "Panacur" and "Safe-Guard", Intervet "Panacur" and "Panacur Rabbit") is a broad spectrum benzimidazole anthelmintic used against gastrointestinal parasites including: giardia, roundworms, hookworms, whipworms, the "Taenia" genus of tapeworms (but not effective against "Dipylidium caninum", a common dog tapeworm), pinworms, aelurostrongylus, paragonimiasis, strongyles and strongyloides and can be administered to sheep, cattle, horses, fish, dogs, cats, rabbits and seals. Drug interactions may occur if salicylanilides like dibromsalan and niclosamide are co-administered.  Abortions in cattle and death in sheep have been reported.

Nosema apis: Nosema apis is a microsporidian, a small, unicellular parasite recently reclassified as a fungus that mainly affects honey bees.  It causes nosemosis, also called nosema, which is the most common and widespread of adult honey bee diseases.  The dormant stage of "N. apis" is a long-lived spore which is resistant to temperature extremes and dehydration, and cannot be killed by freezing the contaminated comb.  Nosemosis is a listed disease with the Office International des Epizooties (OIE).

Glacier flea: The glacier flea ("Desoria saltans", sometimes also "Isotoma saltans") is a species of springtail.  "D. saltans" is "the" common glacier flea, but there are several springtail species that are also called glacier fleas, and which catch the attention on snow surfaces due to their dark body colouring, their hopping motion and the fact that they often gather in large groups.  These include, for example, "Desoria nivalis" (formerly also: "Isotoma pseudomaritima") or "Vertagopus alpinus".

Babesia: Babesia (also called Nuttallia) is an Apicomplexan parasite that infects red blood cells causing a disease known as babesiosis.  Originally discovered by the Romanian bacteriologist Victor Babeș, over 100 species of "Babesia" have been identified, but only a few have been documented to cause disease in humans.

Dipylidium caninum: Dipylidium caninum, also called the flea tapeworm, double-pore tapeworm, or cucumber tapeworm (in reference to the shape of its cucumber-seed-like proglottids, though these also resemble grains of rice or sesame seeds), is a cyclophyllid cestode that infects organisms afflicted with fleas and canine chewing lice, including dogs, cats, and sometimes human pet-owners, especially children.

Capillaria aerophila: Capillaria aerophila is a nematode parasite found in the respiratory tract of foxes, dogs, and various other carnivorous mammals.  A few cases of human infestation have also been reported.  Though it is sometimes called a "lungworm", this term usually refers to other species of nematodes.  Infestation by "C. aerophila" is referred to as "pulmonary capillariasis" (occasionally spelled "capillariosis), "bronchial capillariasis," or (rarely) "thominxosis."  This parasite has a direct life cycle, meaning that the life cycle can be completed in a single host.  "C. aerophila" usually causes only minor clinical symptoms, such as irritation of the respiratory tract and coughing.  However, secondary bacterial infections of the respiratory tract, including pneumonia, may develop in heavy infestations.  Treatment with anthelmintics, such as levamisole or fenbendazole, is usually sufficient to cure "C. aerophila" infestations.

Interspecific pregnancy: Interspecific pregnancy (literally pregnancy between species, also called interspecies pregnancy or xenopregnancy) is the pregnancy involving an embryo or fetus belonging to another species than the carrier.  Strictly, it excludes the situation where the fetus is a hybrid of the carrier and another species, thereby excluding the possibility that the carrier is the biological mother of the offspring.  Strictly, interspecific pregnancy is also distinguished from endoparasitism, where parasite offspring grow inside the organism of another species, not necessarily in the womb.

Echinococcus granulosus: Echinococcus granulosus, also called the hydatid worm, hyper tape-worm or dog tapeworm, is a cyclophyllid cestode that parasitizes the small intestine of canids as an adult, but which has important intermediate hosts such as livestock and humans, where it causes cystic echinococcosis, also known as hydatid disease.  The adult tapeworm ranges in length from 3 mm to 6 mm and has three proglottids ("segments") when intact—an immature proglottid, mature proglottid and a gravid proglottid.  The average number of eggs per gravid proglottid is 823.  Like all cyclophyllideans, "E. granulosus" has four suckers on its scolex ("head"), and "E. granulosus" also has a rostellum with hooks.  Several strains of "E. granulosus" have been identified, and all but two are noted to be infective in humans.

Supporting paragraphs: Fenbendazole Dipylidium caninum
Answer: Dipylidium caninum