多层螺旋CT机架旋转一周获取多幅图像是因为（ ）The reason why the gantry of the multi-slice spiral CT rotates once to obtain multiple images is（ ）
选项：

A:有多个数据采集系统Multi-slice spiral CT has multiple data acquisition systems
B:厚扇形束Thick fan-shaped beam
C:在人体长轴方向有多排探测器Multi-slice spiral CT has multiple rows of detectors in the long axis direction of the human body
D:多层螺旋CT造价高Multi-slice spiral CT is expensive