Paleontologists hypothesize that modern birds evolved from the family of dinosaurs that included Tyrannosaurus rex. This hypothesis would be ply supported if evidence that dinosaurs from this family had a body covering resembling feathers could be found, but so far no such evidence has been found.
Which of the following, if true, would most help the paleontologists explain why no evidence of feathered dinosaurs has yet been found ？（）
A. Fossilized dinosaurs have shown many birdlike characteristics, such as bone structure and winglike arms.
B. If birds are in fact the descendants of dinosaurs, then it can be argued that the dinosaurs never really died out.
C. Flying dinosaurs such as the Pteranodon, which is not thought to have been related to modern birds, do not appear to have had feathers.
D. Soft tissues such as skin and feathers do not fossilize like bones, and therefore are far less likely to have left permanent evidence in the fossil record.
E. The thousands of dinosaur fossils excavated by paleontologists represent only a tiny fraction of the billions of dinosaurs that once lived.