There were a lot of problems with his bike. _______ he sold it and bought a new one.   [ ]

A. At the end

B. In the end

C. By the end

D. To the end

中子寿命测井测量的是（）。

A.中子通量

B.俘获伽马射线

C.非弹性散射伽马射线

D.活化伽马射线