บทสนทนานี้ใช้ตอบคำถามข้อที่41-45

  Hemophilia is an inherited, genetic blood disorder in which one of the proteins--clotting factors--needed to form blood clots in the body is missing or reduced. It has been found in many European royal houses such as Britain, Spain, Germany and Russia.

    Britain's iconic Queen Victoria was a hemophilia carrier and passed on the defective gene to her son, Leopold, and it was carried by many of her daughters. Perhaps more famously, Tsar Nicholas II, who married Queen Victoria's grand-daughter Princess Alexandra, had a son, Tsarevich Alexei Nikolaevic, who suffered from hemophilia. It was controversially claimed that Rasputin, the Russian mystic, healed Alexei's illness.

   Normally, when people have accidents or suffer injuries, the bleeding in the muscles and joints will spontaneously stop. However, in people with hemophilia, the bleeding will last much longer. The severity of hemophilia depends on the amount of clotting factor in the blood. It can range from mild to moderate or life-threatening. In several hemophiliacs, prolonged bleeding from just common injuries or even spontaneous bleeding without obvious cause can last for days and weeks. Worse, it can be lethal if the bleeding occurs in the brain or in joints.

   Bleeding can occur in any part of the body. The joints that are most often affected include the knees, ankles and elbows. If not effectively managed, regular bleeding into the joints can cause joint damage, chronic arthritis and disability. Some hemophiliacs have been crippled by the time they are teenagers due to the effects of bleeding joints.

   There is no cure for hemophilia. However, the condition can be controlled by the constant replacement of the missing or reduced clotting factors. In severe cases, factor injections are administered on a regular basis, usually two to three times a week in order to minimize the likelihood of joint damage. Children with hemophilia these days can live a longer life and enjoy a good quality of life if they receive the proper treatment.

Which word is closest in meaning to "lethal"

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