四、閱讀測驗（18％）：每題 3 分(42~43)        It is autumn. A salmon swims in the sea and looks for the river of her birth. When she gets to the river, sheswims a long way up to her birth place. Days later, she is very tired and dying. But before she dies, she lays hereggs in a safe place in the river.        After a few months, baby salmon come out of the eggs with a yolk sac. The yolk sacs provide food for thebabies for months. When the yolk sacs disappear, the babies become young fish, and they can go find food.The young fish eat small insects and plants.        The salmon live in cold mountain rivers during their early life. After three years, they swim down into thesea. Years later, like their parents, the salmon go back to the river of their birth before winter comes.☺ disappear 消失 lay 產卵 yolk sac 卵黃囊 provide 提供
42. Why do mother salmon swim a long way up the river?
(A) To hide from winter.
(B) To die in a quiet place.
(C) To lay eggs in a safe place.
(D) To find food for their babies.