从A、B、C、D四个选项中，选出可以填入空白处的最佳选项。
At 13 he was sent to a shop, ______ he learned the business.

A．when and how the umbrella was invented
B．why the umbrella was so popular in Europe
C．the development of the umbrella
D．the history and use of the umbrella

A．It is one of the new holiday habits.
B．It is a very interesting way of spending holiday.
C．Camping holidays with tents are very popular in England.
D．The summer weather in England is not fit for camping with tents.