①Socrates(苏格拉底) is the famous ancient Greek thinkers, philosophers(哲学家), educators. On the first day of school, Socrates told his students, "Today, we'll only learn one thing, that is, to stretch(前伸) for your arms, then try to swing(甩动) them back. "He showed them and as a result, all the students laughed. "Sir, is it also learned?" one of the students laughed.
②"Of course! You think this is an easy thing, but in fact, it is very difficult. "Socrates answered seriously(严肃地). Hearing this, all the students laughed even harder.
③Without being a little angry, Socrates said, "In this class I'll teach you how to learn this action well. After that, start today, and you will do it 100 times a day. " 10 days later, Socrates asked, "Who still insists(坚持) on swinging his arms?" About 80% of the students raised their hands. 20days later, Socrates asked again, "Who still insists on swinging his arms?" About 50% of them raised their hands. 3 months later, Socrates asked again, "Who still insists on the simplest action of swinging?" This time, only one student raised his hand. He was Plato.
④From this example, we can see that perseverance is the easiest but the most difficult thing in the world, because everyone can do it, but not everyone will do it. Only the one who can insists on an easy thing may make it!
B . 
C . 
D . 
