The correct option is C A Chinese horse
The phylum Vertebrata is divided into 5 classes- Pisces, Amphibia, Reptilia, Aves, Mammalia. These animals are classified according to their phylogenic relationships as per evolution. Both human and horse belong to the class Mammalia. Hence even if the Indian school boy and Chinese horse belong to different countries, they share a common evolutionary relation. Thus the correct answer is option C.