A common characteristic of all vertebrates without exception is
The division of body into head, neck, trunk and tail
Their body covered with an exoskeleton
The possessive of two pairs of functional appendages
The presence of well-developed skull
The correct option is D The presence of well-developed skull
Vertebrates belong to the subphylum Vertebrata of the Phylum Chordata.
AII vertebrates share a common diagnostic character, the elaboration of
anterior skeletal elements into a "cranium" or "skull' which houses
various sense organs and a complex brain. The distinctive vertebrate
cranium and brain evolved even before the vertebral column and are,
therefore, more fundamental characteristic of vertebrates than the
backbone. So, the correct answer is 'The presence of well-developed skull'.