患者女性，34岁，4年来反复一侧肢体无力，左眼视力下降，眼球活动时疼痛，伴发作性面部感觉异常，有时可自行缓解，激素治疗有效。查体：神清语利，表情焦虑，复视，左眼视力下降，双下肢肌张力增高，右下肢肌力3级，双侧跟膝胫试验不稳，腱反射亢进，病理征阳性，既往体健，否认家族史

头MRI：脑室周围多发散在长T1、T2异常信号，该患者最可能的诊断是（）

A.淋巴瘤

B.脑血管病

C.多发性硬化

D.急性播散性脊髓炎

E.脊髓小脑性共济失调

Which of the following statements about transmitting distress messages by radiotelephone is INCORRECT?（）

A.If no answer is received on the designated distress frequencies，repeat the distress call on any frequency available

B.Channel 16 (156.8) may be used for distress messages

C.It is advisable to follow a distress message on 2182 kHz by two dashes of 10 to 15 seconds duration

D.Distress messages should first be transmitted on 2182 kHz