Which characteristic is unique to vertebrates? A) they all have a well-defined skeleton

B) they have no defined organ systems

C) they have bilateral symmetry

D) they have an exoskeleton
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They have well-defined skeleton.

Explanation:

This is because the vertebrates are uniquely characterised by the presence of the bones.

the transfer of energy between two molecules spaced just nanometers apart plays a key role in many technologies, including photovoltaics, quantum information systems, lighting, and sensors, as well as in biophysics to measure nanometer distances and in photosynthesis. but an open question in this area is what effect, if any, the surrounding photonic environment has on this nanoscale energy transfer. by designing and performing a carefully controlled experiment to answer this question, scientists have settled the debate and found clues to improving the efficiency of many of the technologies that rely on this process.

explanation:

there is no stairs in bungalow

explanation:

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