单选题 The teacher wrote a brief comment in the ______ to show the student why it was wrong.

【正确答案】 B

【答案解析】[解析] 各项的意思是：manual“手册，指南”；margin“页边空白；边缘；余地”；edge“边缘；刀刃；优势；经常指悬崖边上”；verge“边，边缘，界线”；on the verge of“接近于，濒临于”。根据句意判断，答案为B。