A-A+
Which opinion did the discovery prove？A．Modem
问题详情
Which opinion did the discovery prove？
A．Modem birds are the closest living relatives of the two-legged dinosaurs.
B．Dinosaurs have medullary bone.
C．Medullary bone is only known in ovulating birds.
D．Medullary bone is a source of calcium for birds to make shells for their eggs.请帮忙给出正确答案和分析，谢谢！
参考答案
正确答案：A
解析：本题考查对新闻细节的捕捉。根据文中原文"Whattheyfoundwasalayerofsomethingcalledmedullaryboneinsidethethighboneofadinosaurdugupfiveyearsago.”可知科学家们在恐龙化石中发现了一层脊髓骨。接着说明只在产卵的鸟类中发现过这种物质，选项A正确。另外说明脊髓骨是鸟类吸取形成鸟壳的钙质的主要来源。由此可知，脊髓骨中必定富含钙质，选项B、C均正确。因此只有选项D的说法不正确，为本题答案。
