单项选择题

Passage 1  
Nearly a quarter-century after a German boy tossed a message in a bottle off a ship in   the Baltic Sea, he’s received an answer.
A 13-year-old Russian, Daniil Korotkikh, was walking with his parents on a beach when he  saw something glittering lying in the sand.
“I saw that bottle and it looked interesting, ” Korotkikh told The Associated Press on Tuesday.  “It looked like a German beer bottle with a ceramic plug, and there was a message inside.”
His father, who knows a little German, translated the letter. It said: My name is Frank , and  I’m five years old. My dad and I are traveling on a ship to Denmark. If you find thes letter, please  write back to me , and I will write back to you.”
The letter, dated 1987,included an address in the town of Coesfeld.
The boy in the letter, Frank Uesbeck , is now 29. His parents still live at the letter’s address.
“At first I didn’t believe it,” Uesbeck told the AP about getting the response from Korotkikh.  In fact, he barely remembered the trip at all; his father actually wrote the letter.
The Russian boy said he does not believe that the bottle actually spent 24 years in the sea“It  would not have survived in the water all that time,” he said. He believed it bad been hidden under  the sand where he found it . 
In the web chat earlier this month, Uesbek gave Korotkikh his new address to write to and  promised to write back when he receives his letter. 
“He’ll definitely get another letter from me,” the 29-year-old said. 
Uesbeck was especially thrilled that he was able to have a positive impact on a life of a  young person far away from Germany. 

The letter in the bottle was actually written by()

A.Frank
B.Korotkikh
C.Frank’sfather
D.Korotkikh’sfather