问下为啥选BCFor a long time being happy was considered natural,an

问下为啥选B
C
For a long time being happy was considered natural,and there was nothing special to do about it. Now we know that we can work at getting along well with other people. It is possible to act in such a way that other people will like us better.
One way is being unselfish,not wanting everything your own way or asking for the best share of everything, including the attention of your friends. Another way is to look for good points, not bad ones in other people.
You don’t have to be spineless(无骨气的)in order to be popular. In fact,you will be liked and respected(尊重)if you are not afraid to stand up for your rights(权利). But do it politely and pleasantly. One way to develop a good character is being friendly and polite to your own group, to older people,to strangers and especially to those who do not look important or do not interest you.
You cannot expect to be perfect, so you must learn not to be too unhappy when you make a mistake. Everyone makes mistakes, and no one is to be blamed unless he refuses to learn from them. Many young people become discouraged(泄气的) when they know their unpleasant qualities—selfishness,laziness,etc. Just remember that we all have some of these faults and have to fight against them.
When sometMng is wrong,it is best to try to make it right. Perhaps you don’t like a teacher or a classmate. Try to see why,and look at yourself,too. Make sure that you are not doing something to make others dislike you. In time, things may turn out all right, then you simply have to learn to get along the best you can with the situation, without thinking too much about it. Worrying never helps in a situation you can’t change.
29．What can we know from the passage?
A.Even if we don’t have good relationships with others,we needn’t work at it.
B.Even if someone is not important to us,we still need to treat him politely.
C.Even if we are willing to learn from ouy mistakes,we are still to be blamed.
D.Even if the situation cannot be changed, we still need to worry much about it.