Question

Bat is a mammal because
(a) Bat having wing like a bird
(b) Bat having a tail like other mammals
(c) Bat is a hot blooded animal
(d) Bat has a milk-secreting gland

Answer 1

It is the only group of mammals capable of flight. This ability, including the power to navigate in the dark by employing a system of acoustic orientation (echolocation), has made the bats a highly diverse and populous order. Wing proportions are modified according to the mode of flight.

Complete answer:
Bat is put in class Mammalia since they bring forth a live youthful one who makes due by sucking milk from mammary organs through areolas. The mammary organs are the exocrine organ that produces milk to nourish the baby and they are discovered uniquely in class Mammalia of the whole animal kingdom.
The taxonomic classification of the bat is:
Kingdom: Animalia
Phylum: Chordata
Subphylum: Vertebrata
Class: Mammalia
Order: Chiroptera

Additional Information: All bats have a generally similar appearance on the wing, dominated by the expanse of the wings, but they vary considerably in size. The order is typically divided into two well-defined suborders: the Megachiroptera (the large Old World fruit bats) and therefore the Microchiroptera (small bats found worldwide). The flying foxes (Pteropus) have a wingspan of 1.5 meters (around 5 feet) and a load of 1 kg (2.2 pounds) among individuals from the Megachiroptera. The biggest insectivorous bat is maybe the bare, or bare, bat (Cheiromeles torquatus); it weighs around 250 grams (around 9 ounces). The largest of the carnivorous bats (and the most important bat within the New World) is the spectral bat (Vampyrum spectrum), also known as the tropical American false vampire bat, with a wingspan of approx 60 cm (24 inches). The tiny hog-nosed, or bumblebee, bat (Craseonycteris thonglongyai) of Thailand is one of the littlest mammals.
So the correct answer to the above question is ‘Bat has a milk-secreting gland’.

Note: Bats vary in color and in fur texture. Facial appearance, overwhelmed by the muzzle and ears, changes strikingly among families and at times between genera. In several families, a posh fleshy adornment called the nose leaf surrounds the nostrils.