Question

Which one of the following groups of animals is correctly matched with its one characteristic feature without even a single exception?

• A. Mammalia: Give birth to young ones
• B. Reptilia: Possess 3-chambered heart with one incompletely divided ventricle
• C. Chordata: Possess a mouth provided with an upper and a lower jaw
• D. Chondrichthyes: Possess cartilaginous endoskeleton

Answer 1

The correct option is D Chondrichthyes: Possess cartilaginous endoskeleton

Mammals are mostly viviparous but primitive mammals like platypus lay eggs. Reptiles have mostly three chambered heart but the heart of crocodile is four-chambered. Primitive chordates like Agnatha (cyclostomes) do not have well developed jaw but all Chondrichthyes animals have cartilaginous endoskeleton without exception. They have the flexible skeleton as it is made up of cartilage such as shark. Thus, the correct answer is option D.