单选题根据下面的内容，回答题.


We can tell from the results of the poll that

A．people are unconcerned about politeness nowadays.
B．"thank you" remains the best expression of gratitude.
C．there is a variety of expressions of appreciation.
D．there are more formal expressions than informal ones.

A．Thanks.
B．Cheers.
C．Brilliant.
D．You star.

A．Thanks.
B．Cheers.
C．Nice one.
D．Sure.