—I think I won’t pass the exam, and my parents will be angry with me.

—_____________. You have tried your best.

A．Well done.

B．That’s all right.

C．Take it easy.

D．No problem.

患者30岁，右前臂见一界限清楚的肿物，大小2cm×1．5cm×1．5cm，有轻微的麻木感和放射性痛，镜下大部分区域为波浪状纤细的梭形细胞伴黏液变性。

免疫组化蛋白标记阳性的是（）

A.S-100

B.LCA

C.CK

D.Desmin

E.CD20