The contract between a party who agrees to accept the risk and a party seeking protection from the risk a contract of_______

A．payment
B．production
C．shipment
D．insurance

CT扫描时，球管旋转数秒后停止，检查床移到下一个扫描层面，重复进行下一次扫描的扫描方式是（）

A.常规扫描

B.螺旋扫描

C.间隔扫描

D.持续扫描

E.高速扫描