1.        GWD-3-Q9x:

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?

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

2. 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.

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

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

5. 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

为什么 D 不对么?

i think B reminds people the CC obligation, which sometimes can reduce the money people are willing to spend...

stil confused

this question need us to find a choice that will support the explaination by psychologists

Psychologists think that the credit-card logo help the customers remind of thire protential spending power.So they leave tips much more than before.

Chioce D is out of scope.Argument above invloves only one kind of person who who pay their bill in cash .They will leave more tips than usual when they were informed their protential spending power by the credit-card logo presented on the tray. 

B is the  answer.

That's the pattern:A-->B

SUPPORT PATTEN: no A---> no B