What is the author's attitude towards the" 10-minute cup of coffee" method

A．How to communicate in management and why it is important.
B．How to become an effective and successful manager.
C．How to save time and be efficient in management.
D．How to understand customers and solicit employees' ideas.

A．The necessity of spending time with customers has not been proved.
B．The advantages of spending time with customers are not obvious.
C．Managers may benefit a lot from pay a visit to their customers.
D．More and more managers begin to spend time with customers.