(单选题)

In big toy companies, ________is serious business.

A.playing games

B.inventing toys

C.locking rooms

D.stealing ideas

参考答案：B

参考解析：

细节理解题。根据第一段第一、二句“Toys and games are fun, but inventing them is serious business. Big toy companies treat it even more serious”可知，在大型玩具公司，发明玩具是一件严肃的事。故选B。

知识点：阅读理解四选一英语专业基础知识阅读理解教师招聘-小学英语