听力原文:The idea of permanent education is practical because people are never really too

听力原文：The idea of permanent education is practical because people are never really too old to go on learning．Of course there are certain limits but these are not age limits.

Permanent education is practical because______.

A．there are no limits at all.

B．there are no age limits.

C．no one is getting really too old.

D．no one wants to learn at old age.

请帮忙给出正确答案和分析，谢谢！