Im thinking this is cause and effect reasoning because it says that credit card logos cause people to spend more
Cc logo -> SPEC-> More tip ( spending power exceeds case)
The credit card logo causes people to think they have more spending power which in turn causes them to leave more tip.
we could strengthen the argument by showing
1.when the cause doesnt occur the effect does not occur
2. when the cause occurs the effect occurs
3. Eliminate alternative causes.
4. the relationship is not reversed.
5. good statistics
So lets look at the answer choices
A. Does not effect the relationship at all ( Whether you have a credit card or not is not problem with the study)
B. Is the right answer. ( when the cause does not occur the effect does not occur. When you are reminded that your spending power DOES NOT
exceed you dont leave as big a tip.
C. If anything this answer might weaken the argument.
D. Does not effect the relationship in anyway.
E. Same As D ( irrelevant).
Ps. Kudos are always welcomed ; )