CO2对呼吸运动的调节作用，最主要是通过刺激
A．主动脉体和颈动脉体化学感受器B．延髓呼吸中枢C．延髓化学感受器D．脑桥呼吸调整中枢
参考答案：C
In relation to the formation of a contract in the context of the UN Convention for the International Sale of Goods, explain:
(a) the meaning of an offer; (5 marks)
绝缘子是（）元件。
A.电容
B.电感
C.电阻
D.电导
