问题
颅脑增强MRI扫描一般在注射对比剂 ______分钟后开始行增强扫描
A.2
B.5
C.3
D.4
E.10
请帮忙给出正确答案和分析，谢谢！
Fatal error: Uncaught [XSException] ../../../usr/local/xunsearch/sdk/php/lib/XS.php(2559): Connection refused(C#111, localhost:8384)
thrown in /usr/local/xunsearch/sdk/php/lib/XS.php on line 2559
