Nowadays, the younger generations are often complained about the selfishness and lack of respect by the older generations. It is undeniable that some young people do need to be educated on mutual   respect and concern for others, especially senior members of society. But we older people should have some understanding about the young, too. Today's society is rather different from what it was when we were young. The social, financial and psychological pressure today's young people have to face is much higher than what we did back in the 1950s through the 1990s.   They are in the early stage of their career. They have to find proper jobs to support themselves and work hard to rise. They have to live in smaller houses, because they are unable to afford the rising housing prices. Considering these facts, we may find it understandable why young people sometimes appear aloof   and disrespectful. I don't mean that we should put up with it without reminding them of the need to mend their ways. What I mean is that we should be more patient, understanding and tolerant toward them.  For instance, when we get up on a bus or a subway train, we should not complain about not being offered a seat. A young person does not offer a senior citizen his/her seat probably because he/she has to travel a long way to work or because the carriage is too crowded for one to move at all.  In fact, young people do offer their seats to the seniors. I seldom take a bus or a subway train, but more than a quarter of the times I have done so, I was offered a seat. That is fair enough, considering that I do not look so old. But on occasions, I have seen old people not showing any sign of gratitude when offered a seat.   China has become an aging society since the end of the last century. According to a recent survey, people older than 60 accounted for 11.4 percent of the nation's population. And the percentage is expected to rise because of the one-child family planning policy our country has practiced for more than three decades.   In other words, the younger generations will have to shoulder a heavier burden in looking after the parents and grandparents. Theoretically, there will come a day when one couple may have to support four parents and eight grandparents. What a burden it would be!   All this require that we should show more concern and understanding to our younger generations. How is the passage mainly developed?
By comparing. By reasoning. By listing examples. By following the natural time order.
Question: Nowadays, the younger generations are often complained about the selfishness and lack of respect by the older generations. It is undeniable that some young people do need to be educated on mutual   respect and concern for others, especially senior members of society. But we older people should have some understanding about the young, too. Today's society is rather different from what it was when we were young. The social, financial and psychological pressure today's young people have to face is much higher than what we did back in the 1950s through the 1990s.   They are in the early stage of their career. They have to find proper jobs to support themselves and work hard to rise. They have to live in smaller houses, because they are unable to afford the rising housing prices. Considering these facts, we may find it understandable why young people sometimes appear aloof   and disrespectful. I don't mean that we should put up with it without reminding them of the need to mend their ways. What I mean is that we should be more patient, understanding and tolerant toward them.  For instance, when we get up on a bus or a subway train, we should not complain about not being offered a seat. A young person does not offer a senior citizen his/her seat probably because he/she has to travel a long way to work or because the carriage is too crowded for one to move at all.  In fact, young people do offer their seats to the seniors. I seldom take a bus or a subway train, but more than a quarter of the times I have done so, I was offered a seat. That is fair enough, considering that I do not look so old. But on occasions, I have seen old people not showing any sign of gratitude when offered a seat.   China has become an aging society since the end of the last century. According to a recent survey, people older than 60 accounted for 11.4 percent of the nation's population. And the percentage is expected to rise because of the one-child family planning policy our country has practiced for more than three decades.   In other words, the younger generations will have to shoulder a heavier burden in looking after the parents and grandparents. Theoretically, there will come a day when one couple may have to support four parents and eight grandparents. What a burden it would be!   All this require that we should show more concern and understanding to our younger generations. How is the passage mainly developed?
A. By comparing.
B. By reasoning.
C. By listing examples.
D. By following the natural time order.
Answer: