问题
选择题
_____ three times in a row, the boxer decided to give up fighting. [ ]
A. Having defeated
B. To have defeated
C. Having been defeated
D. To have been defeated
答案
答案：C
搜题请搜索小程序“爱下问搜题”
_____ three times in a row, the boxer decided to give up fighting. [ ]
A. Having defeated
B. To have defeated
C. Having been defeated
D. To have been defeated
答案：C
（二）资料
| 目前许多大学生毕业后不是直接参加工作，而是继续读研究生。请你运用人力资本投资的有关理论，完成下列问题。 |
在其他条件相同的情况下，投资后的收入增量流越长，则一项人力资本投资的净现值越可能为( )。
A．正
B．负
C．零
D．以上都不对