People with disabilities make up a large part of the population. It is estimated（估计） that over 35 million Americans have physical, mental, or other disabilities. About half of these disabilities are “developmental", i.e., they occur before the individual's twenty-second birthday, often from genetic conditions, and are severe enough to affect three or more areas of development, such as mobility, communication, employment, etc. Most other disabilities are considered “adventitious", i.e., accidental or caused by outside forces.
Prior to the 20th century, only a small percentage of people with disabilities survived for long. Medical treatment for these disabilities was unavailable. Advancements in medicine and social services have created a climate in which people with disabilities can expect to have such basic needs as food, shelter, and medical treatment. Unfortunately, these basics are often not available. Civil liberties such as the right to vote, marry, get an education, and gain employment have historically been denied on the basis of disability.
In recent decades, the disability rights movement has been organized to fight against these infringements（违反；侵犯）of civil rights. Congress responded by passing major legislation recognizing people with disabilities as a protected class under civil rights statutes.
Still today, people with disabilities must fight to live their lives independently. It is estimated that more than half of qualified Americans with disabilities are unemployed, and a majority of those who do work are underemployed. About two-thirds live at or below the official poverty level.
Significant barriers, especially in transportation and public awareness, prevent disabled people from taking part in society. For example, while no longer prohibited by law from marrying, a person with no access to transportation is effectively excluded from community and social activities which might lead to the development of long-term relationships.
Only when public attitudes advance as far as laws have will disabled people be fully able to take their rightful place in society.
A “developmental" disability ______.

A．develops very slowly over time

B．is caused by forces

C．occurs in youth and affects development

D．is getting more and more severe

Most disabled people used to die early because ______.

A．disabilities destroyed major bodily functions

B．they were not very well looked after

C．medical techniques were not available

D．they were too poor to get proper treatment

In the author's opinion, to enable the disabled people to take their rightful place in society, ______.

A．more laws should be passed

B．public attitudes should be changed

C．government should provide more aids

D．more public facilities should be set up

Which of the following cannot be inferred from the passage ?

A．Many disabled people may remain single for their whole life.

B．The public tends to look down upon the disabled people.

C．The disabled people feel inferior to those surrounding them.

D．Discriminatory laws prevent the disabled from mixing with others.

The best title for this passage might be ______.

A．Handicaps（障碍）of People with Disabilities

B．The physical difficulties of the Disabled

C．The Causes for Disabilities

D．Medical Treatments for Disabilities