没有讨论过的GWD5-Q31

GWD5-Q31:

Studies in restaurants show that the
tips left by customers who pay their bill in cash tend to be larger when the
bill is presented on a tray that bears a credit-card logo.  Consumer psychologists hypothesize that
simply seeing a credit-card logo makes many credit-card holders willing to
spend more because it reminds them that their spending power exceeds the cash
they have immediately available.

Which of the following, if true,
most strongly supports the psychologists’ interpretation of the studies?

A.     
The effect noted in the studies is not limited to patrons
who have credit cards.

B.      
Patrons who are under financial pressure from their
credit-card obligations tend to tip less when presented with a restaurant bill
on a tray with credit-card logo than when the tray has no logo.

C.     
In virtually all of the cases in the studies, the patrons
who paid bills in cash did not possess credit cards.

D.     
In general, restaurant patrons who pay their bills in cash
leave larger tips than do those who pay by credit card.

E.      
The percentage of restaurant bills paid with given brand of
credit card increases when that credit card’s logo is displayed on the tray
with which the bill is prepared.

正确答案是B.可是我怎么觉得B不对呢。题目是说结帐时托盘有信用卡logo时，顾客会多付小费。 问ABCD那个支持该结论，B选项意思正相反呀。呼唤高人解释。