Which of the following characteristic features always holds true for the corresponding group of animals
`{:("(a)","Cartilagious endoskeleton",,"Chondrichthyes"),("(b)","Vivparous",,"Mammalia"),("(c)","Possess a mouth with an upper and a lower jaw",,"Chordata"),("(d)","3- chambered heart with one incompletely divided ventricle",,"Reptilia"):}`
A. `{:("Viviparous "," Mammalia "):}`
B. `{:("Possess a mouth"," Chordata"),("with an upper and a ",""),("lower jaw",""):}`
C. `{:("3- chambered heart"," Reptilia"),("with one incompletely",""),("divided ventricle",""):}`
D. `{:("Cartilaginous"," Chondrichthyes"),("endoskeleton",""):}`
