单选题 Sea horses have unusual parents. The female sea horses lay the eggs, but unlike other creatures. It's the males that give birth to the young.
Male sea horses have a fold of skin on their bellies that forms a pocket, called a brood pouch. During the breeding season, the sea horse's pouch swells to receive eggs. A female sea horse lays Up to 200 eggs at a time in the pouch. Then she swims off, leaving her male partner to care for the developing eggs and give birth to young sea horses. The female will return every day to check on her mate and the eggs, but she doesn't stay long, nor does she take part in the birth.
It takes from five to six weeks for the eggs in the male' s pouch to develop. During this time the male avoids open water and hides in sea grass. His big pouch makes it difficult from him to swim, so the male often uses his tail to grasp a piece of sea grass. Firmly, gripping the grass, he will stay perfectly still for hours or even days. The male sea horse will change his color to blend with his surroundings and avoid being seen by predators who will try to eat him or poke holes in his pouch to get the eggs.
The eggs hatch inside the male's pouch. When the babies begin moving around, the male sea horse knows it's time for them to be born. He grabs a sea grass stern with his tail and begins rocking, bending his body back and forth, this causes the opening to enlarge until wide enough for the first baby sea horse to shoot out. the father sea horse continues rocking, bending, and stretching his body so that the rest of the babies can be born. Sometimes he has to press his pouch against a rock or some stiff seaweed to force the young out.
Sea horse babies are born in groups of five or more. Sometimes it takes two clays for the father sea horse to give birth to all his young. He is very tiered when it's over.
Soon after giving birth to one brood, the male will approach his mat and show her his empty pouch. This tells her he is ready to receive eggs again.

单选题 What part does the female sea horse play in having babies?

A. Receive eggs.
B. Laying eggs.
C. Hatching eggs.
D. Protecting eggs.

【正确答案】 B

【答案解析】[解析] 从第一段第二句讲到雌海马负责生蛋，公海马负责孵育，故答案选B。

单选题 What can be learned from the passage about giving birth to baby sea horse?

A. It is dangerous for female.
B. It happens once a year.
C. It is hard work for the male.
D. It occurs in the deep sea.

【正确答案】 C

【答案解析】[解析] 整篇文章都在讲公海马孵育小海马的过程，只有选项C符合文意，故答案选C。

单选题 To protect himself and his eggs, the male sea horse does all the following EXCEPT ______.

A. changing his color
B. gripping a piece of grass
C. staying motionless
D. enlarging his pouch

【正确答案】 D

【答案解析】[解析] 第三段讲了公海马在孵育小海马时是如何自我保护的，选项D没有提到。故答案选D。

单选题 The author suggests when sea horse babies are ready to be born ______.

A. the male sea horse seems very happy
B. it is difficult for them to come out
C. the female sea horse joins the male
D. they need large space in the pouch

【正确答案】 B

【答案解析】[解析] 第四段讲述公海马孵育小海马的最后阶段，摇摆身体或者挤压育儿袋等，使袋口撑大，便于小海马出来，由此可以看出小海马从育儿袋出来不太容易，故答案选B。

单选题 Which fact does the author want the reader to remember most?

A. The male sea horse gives birth to the young.
B. The female sea horse lays up to 200 eggs at a time.
C. Baby sea horses are born in groups of five or more.
D. The female will return every day to check on the eggs.

【正确答案】 A

【答案解析】[解析] 全文讲述了公海马从开始孵育小海马，到孵育出小海马的过程，与其他动物都不相同，一切工作都是公海马所做，这也正是本文的主要写作目的，故答案选A。