Information: - Waders are birds commonly found along shorelines and mudflats that wade in order to forage for food (such as insects or crustaceans) in the mud or sand. They are called shorebirds in North America (where "wader" is used to refer to long-legged wading birds such as storks and herons). Waders are members of the order Charadriiformes, which includes gulls, auks and their allies. - Crocodiles (subfamily Crocodylinae) or true crocodiles are large aquatic reptiles that live throughout the tropics in Africa, Asia, the Americas and Australia. Crocodylinae, all of whose members are considered true crocodiles, is classified as a biological subfamily. A broader sense of the term crocodile, Crocodylidae that includes "Tomistoma", is not used in this article. The term crocodile here applies only to the species within the subfamily of Crocodylinae. The term is sometimes used even more loosely to include all extant members of the order Crocodilia, which includes "Tomistoma", the alligators and caimans (family Alligatoridae), the gharials (family Gavialidae), and all other living and fossil Crocodylomorpha. - The pratincoles or greywaders are a group of birds which together with the coursers and Egyptian plover make up the family Glareolidae . They have short legs , very long pointed wings and long forked tails . - Glareolidae is a family of birds in the wader suborder Charadri. It contains two distinct groups, the pratincoles and the coursers. The atypical Egyptian plover ("Pluvianus aegyptius"), traditionally placed in this family, is now known to be only distantly related. - The Egyptian plover ("Pluvianus aegyptius"), also known as the crocodile bird, is a wader, the only member of the genus "Pluvianus". Formerly placed in the pratincole and courser family, Glareolidae, it is now regarded as the sole member of its own monotypic family Pluvianidae. - Plovers (or ) are a widely distributed group of wading birds belonging to the subfamily Charadriinae. - The coursers are a group of birds which together with the pratincoles make up the family Glareolidae. They have long legs, short wings and long pointed bills which curve downwards. Their most unusual feature for birds classed as waders is that they inhabit deserts and similar arid regions. - Birds (Aves), also known as avian dinosaurs, are a group of endothermic vertebrates, characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a lightweight but strong skeleton. Birds live worldwide and range in size from the bee hummingbird to the ostrich. They rank as the class of tetrapods with the most living species, at approximately ten thousand, with more than half of these being passerines, sometimes known as perching birds or, less accurately, as songbirds. Given the information above, choose from the list below the object entity that exhibits the relation 'taxon rank' with the subject 'pratincole'. Choices: - class - family - genus - group - order - subfamily - suborder
The answer to this question is:
subfamily