A、They allow it to maneuver effectively in a small areas. B、They allow it to swim quickly over long distances. C、Dorsal and pect

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问题  
Today we are going to talk about a species of fish that is rather unique: Today’s lecture is about sea horses, if you’ve seen a sea horse, you may have noted that it has a horse-like head attached to its body. The sea horse has a long snout that is good for sucking. Instead of scales like most fish, sea horses have skin that is stretched over bony plates. The body extends to a prehensile tail, meaning that the tail can be used to grasp. The sea horse may grasp sea grass or coral to keep it stable in a moving current.
    The sea horse has fins on its back that it can use to propel it through the water. However, sea horses aren’t very good swimmers. They do not move quickly over great distances. The sea horse also has chest fins that it uses for stabilization. The chest fins help the sea horse float in an upright position.
    One particularly unique feature of sea horse is that only the male becomes pregnant. The female inserts ripe eggs into the male’ pouch, where they are fertilized. The eggs become embedded in the pouch wall.

选项 A、They allow it to maneuver effectively in a small areas.
B、They allow it to swim quickly over long distances.
C、Dorsal and pectoral fins have no function in sea horse.
D、Their multi-colored fins attract shrimp and other food.

答案A

解析 该题难度较大。题干关键词“dorsal and pectoral fins”对于考生来说不熟悉,但其实就是文中所提及的“fins on the back”和“chest fins”,需要考生自.己推理。另外正确选项a也并不是从原文可以直接听取的,是需要依靠逻辑推理的。选项b只是涉及了部分内容。
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