61. Which of the following is a typical symptom of the bends?
A. A twisted body.
B. A gradual decrease in blood supply.
C. A sudden release of nitrogen in blood.
D. A drop in blood pressure.
62. The purpose of Rothschild's study is to see ______.
A. how often ichthyosaurs caught the bends
B. how ichthyosaurs adapted to decompression
C. why ichthyosaurs bent their bodies
D. when ichthyosaurs broke their bones
63. Rothschild's finding stated in Paragraph 4 ______.
A. confirmed his assumption
B. speeded up his research process
C. disagreed with his assumption
D. changed his research objectives
64. Rothschild might have concluded that ichthyosaurs ______.
A. failed to evolve an anti-decompression means
B. gradually developed measures against the bends
C. died out because of large sharks and crocodiles
D. evolved an anti-decompression means but soon lost it