—Could you finish the task in two days? 

—_______. I have something else to do these days. [ ]

A. I could not

B. Yes, I thinks so

C. I'm afraid so

D. I'm afraid not

对于肺良性与恶性结节的诊断及肺癌分期（）。

A.X线正侧位胸片

B.CT扫描

C.核素

D.MRI检查

E.经皮胸腔穿刺肺活检