始祖鸟具有爬行类和鸟类之间的过渡形态，其所具有的鸟类的形态特征包括：（）
A. 具有开放式骨盆
B. 双凹形椎体
C. 前肢三指分离，各自具爪
D. 后肢四趾，三前一后
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保卫祖国、抵抗侵略中华人民共和国每一个公民的神圣职责。
A. 正确
B. 错误
世界上诞生最早的现代意义上的夜视器材是主动红外夜视仪。
A. 正确
B. 错误
提高酸液的粘度可以降低氢离子的传质系数，有利于提高酸化效果。
A. 正确
B. 错误
Fuel oil transfer systems used onboard diesel propelled vessels are required to have （）.
A. two fuel oil transfer pumps provided where one is to be independent of the main engine
B. two fuel oil transfer pumps, with a combined capacity exceeding the maximum consumption of the main engine
C. engine driven transfer pumps and only used in constant speed applications
D. the capacity of the engine driven pump exceed the consumption rate of the engine to which it is attached
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