单选题
The liver is the second largest organ in your body. The liver performs many jobs in your body. It processes what you eat and drink into energy and nutrients your body can use. The liver also removes harmful substances from your blood.
One out of every 10 Americans is affected by liver disease. Liver disease is one of the top 10 causes of death in the United States. There are more than 100 liver diseases. Viruses cause some of them, like hepatitis A, hepatitis B and hepatitis C. Others can be the result of drugs, poisons or drinking too much alcohol. If the liver forms scar tissue because of an illness, it"s called cirrhosis. Cancer can affect the liver. You should also inherit a liver disease such as hemochromatosis.
Liver disease can manifest in many ways. Characteristic manifestations include jaundice, liver enlargement, portal hypertension and etc. Sometimes the manifestations of liver disease are not obvious. For example, symptoms may include fatigue, a general feeling of illness, loss of appetite, and mild weight loss. However, people may not notice these symptoms, and these symptoms are also typical of many other diseases. Thus, liver disease can easily be overlooked, particularly in its early stages.
Hepatitis A vaccination is the best way to prevent HAV (hepatitis A virus). Hepatitis B vaccination is the best way to prevent HBV. Other ways to stop the spread of HBV are: not sharing needles; practicing safe sex; not Sharing razors, toothbrushes, or other personal items; using only clean needles for fattoos and body piercings. There is no vaccine to prevent HCV. The only way to prevent HCV is to avoid direct contact with infected blood.
Eating a healthy diet and exercising regularly help the liver to work well. Limit the amount of alcohol you drink. When medicines are taken incorrectly, the liver can be harmed. So follow dosing instructions and talk to a doctor or pharmacist about the medicines you are taking. Mixing alcohol and medicines can harm your liver, even if they are not taken at the same time. Toxins can injure liver cells. So limit direct contact with toxins from cleaning and aerosol products, insecticides, chemicals, and additives in cigarettes. Do not smoke.

单选题 Which of the following statements is NOT true according to the passage?

单选题 The word "manifest" in Paragraph 3 can be best replaced by ______.

单选题 Unobvious symptoms of liver diseases may include the following signs EXCEPT ______.

单选题 Which of the following statements is true according to the passage?

单选题 The main purpose of this passage is to let people know ______.