TOEFL Reading: ETS-TOEFL阅读机经 - 36C5H35AT9R6IS7NL$

Which of the following is mentioned in paragraph 3 as a disadvantage of the hard eggshell A. It increased the hatching period. B. It prevented the development of large-size eggs. C. It made it more difficult for the embryo to obtain water. D. It made it harder for the embryo to survive until hatching.