雀斑与雀斑样痣的鉴别中符合雀斑的是（）。

A.颜色较深

B.日晒后增多

C.任何部位均可发病

D.病理为黑素细胞数目增多

E.与日晒无关

It______ a calm head to find the best solution to such a difficult problem within a short time.

A．costs

B．takes

C．spends

D．needs