阅读短文，根据短文内容，从短文后的五个选项中选出能填入空白处的最佳选项。选项中有一项为多余选项。
A．The Italian was afraid
B．It was the Italian’s watch
C．He decided to follow him
D．The Frenchman got excited
E. The street was dark and quiet
A Frenchman went to a small Italian town and was staying with his wife at the best hotel there. One night, he went out for a walk alone. It was late. ____ . Suddenly he felt someone behind him. He turned his head and saw an Italian young man who quickly walked past him. The man was nearly out of sight when the Frenchman suddenly found that his watch was gone. He thought that it must be the Italian who had taken his watch. ____ because he wanted to get back the watch.
Soon the Frenchman caught up with the Italian. Neither of them understood the other’s language. The Frenchman shook his fist(拳头) in the Italian's face and pointed at the watch.____ . In the end he gave up his watch to the Frenchman.
When he returned to the hotel, the Frenchman told his wife what had happened. He was greatly surprised when his wife pointed to the watch on the table. Now he realized that by mistake he had robbed(抢劫) the Italian. ____ .
，其前15项的和等于
，这种数列有（ ）
