【单选题】

Hitherto, there is no evidence yet that would definitively prove whether or not some dinosaurs were warm-blooded, but scientists have begun to investigate　oxygen isotopic abundances in the annual growth bands of teeth or bones of high Line latitude, hence seasonally influenced, terrestrial dinosaurs. The ratio of oxygen isotopes depends on temperature, and an absence of seasonal variations in oxygen 18―a heavy version of the common oxygen 16 atom―would　strongly suggest that the animals maintained a constant internal　temperatures. Such a finding would not, however, constitute "proof"　that dinosaurs were warm blooded, as there are external mechanisms that cold-blooded animals employ to　regulate body temperatures and thereby influence metabolic rates. More nettlesome is that proof would have to come from discovery of intact dinosaur remains in which the soft tissue had not been replaced or altered, and from which the biomolecules responsible for thermoregulation could be extracted identified and characterizeD、Such a proof is unlikely, as it would require an　almost impossible level of preservation over 65 million years, plus the advent of biotechnology that does not yet exist. The author’’s primary purpose is to________.

A、answer a theoretical question in the field of dinosaur thermoregulation
B．discuss the current state of research in the field of dinosaur thermoregulation
C．resolve a dispute in the field of dinosaur thermoregulation research
D．predict a future crisis in the field of dinosaur thermoregulation research
E．suggest some of the possible benefits of a technique in dinosaur thermoregulation research