题目内容：

请阅读下列短文，从每题所给的四个选项(A、B、C和D)中，选出最佳选项。

Five Things You Should Know About Adult Asthma (哮喘)

About 44 million people in Asia Pacific suffer from asthma．The numbers are on the rise especially in China and India where there is rapid industrialization and urbanization．Dr Mariko Koh, Director of the Pulmonary Function Laboratory and Asthma Programme at Singapore General Hospital, tells us more about adult asthma:

1．Chronic inflammation (炎症) of the airways

When the airways are inflamed, mucus (粘液) forms, blocking airflow, causing breathlessness, wheezing (喘息) and tightness in the chest.

2．Common triggers

Exposure to allergens (过敏原) such as mites, cockroaches, pets and pollen can trigger asthma．Tobacco smoke, respiratory infections, exercise and some medications like aspirin and beta blockers are also possible triggers.

3．Effective treatment

Asthma can be controlled with medication．The main treatment of asthma is inhaled(吸入)corticosteroids to reduce inflammation and block of the airways．Reliever medications may be used to treat acute symptoms．Take note: it is not too late to take medication after an asthma attack.

4．Take medication daily

To ensure good control over asthma, medication must be taken daily on a long term basis to prevent attacks．Also, go to your doctor for regular checkups.

5．Quality of life

Asthma sufferers can lead normal active lives as long as the symptoms are well controlled．Taking medication as directed and avoiding triggers can make a big difference to the quality of life.

1.All of the following are possible factors causing asthma except _________.

A．aspirin

B．pollen

C．polluted air

D．tobacco

2.What can be inferred from the passage?

A．There is no possible cure for allergic asthma．

B．Asthma is caused by acute inflammation of the airways.

C．China and India have the largest number of asthma sufferers in the world．

D．Regular checkups and exercise can ensure you a life free from asthma symptoms.

3.The author would most likely to agree that __________.

A．asthma sufferers can lead a normal life as ordinary people

B．daily intake of medication in the long run is helpful in controlling asthma

C．rapid industrialization and urbanization are the leading causes of asthma

D．once asthma attacks, it is too late to take medication

4.What is the purpose of this passage?

A．To explain the cause of asthma

B．To stress the importance of keeping away from asthma

C．To confirm a successful research about asthma

D．To inform readers several aspects about asthma