Answer:
The correct answer is option a.
Step-by-step explanation:
The paleontologists witness Archaeopteryx as an intermediate fossil in between the modern birds and dinosaurs. With its amalgamation of reptilian and avian characteristics, it was long considered as the primitive known bird. Thus, when one witnesses a dinosaur fossil in the field and finds that the fossil is covered in fossils, it can be concluded that it is an Archaeopteryx.