使用“标注”工具栏中的（ ）按钮，可以在已注尺寸数字中添加文本，如直径符号 f 。

A、<IMG src="https://s3.cn-north-1.amazonaws.com.cn/qingshuxuetang/staticQuestionImg/ee491694-b91a-4445-82fc-2978005fe4ca.jpg"title="ex_1318235121958_0.jpg" alt="ex_1318235121958_0.jpg"/>

B、<IMG src="https://s3.cn-north-1.amazonaws.com.cn/qingshuxuetang/staticQuestionImg/8807dbec-f32a-4867-9fc4-888386bfaacf.jpg"title="ex_1318235130999_0.jpg" alt="ex_1318235130999_0.jpg"/>

C、<IMG src="https://s3.cn-north-1.amazonaws.com.cn/qingshuxuetang/staticQuestionImg/81c856f1-7e33-4a42-b048-a213ea693ef3.jpg"title="ex_1318235139393_0.jpg" alt="ex_1318235139393_0.jpg"/>

D、<IMG src="https://s3.cn-north-1.amazonaws.com.cn/qingshuxuetang/staticQuestionImg/c81125a1-d18c-4366-a4f6-42b00be60223.jpg"title="ex_1318235149142_0.jpg" alt="ex_1318235149142_0.jpg"/>