The author thinks it is also very important to make sure ______.

A．He doesn't sell tea or washing powder any more.
B．He must try hard to remember the names of the regular customers.
C．He has to give advice and makes decisions when problems arise.
D．He has to take care of a large staff as well as business.

A．how the supermarket has replaced the old general store
B．how the old-fashioned general store is fast disappearing
C．how supermarket managers deal with problems every morning
D．how the role of the shop manager has undergone an overall change